ACT 2 Math Level 1 · ClipSAT

⏱ Exam Timer: 00:00
New

ACT 2 Math Level 1

Provider · ACT Inc. Format · Subject Test · Advanced Chapters · 8 Level · Pre-calculus & beyond
i

Test format & strategy

🗻 ACT Math Advanced — Score Range 28–36 Topics
Reporting Category % of Test Key Topics
Advanced Number Theory ~8% Sequences, integer properties, modular arithmetic, complex numbers
Advanced Algebra ~15% Polynomial systems, rational equations, logarithms, exponentials
Advanced Functions ~15% Piecewise, recursive, parametric, function composition chains
Advanced Trigonometry ~10% Radians, unit circle, identities, inverse trig, law of sines/cosines
Pre-Calculus Concepts ~12% Limits (informal), sequences/series, conic sections, polar basics
Advanced Coordinate Geometry ~10% Conic equations, transformations, distance in 3D
Advanced Plane Geometry ~10% Circle theorems, similarity, 3D solids, geometric proof
Statistics, Counting & Probability ~10% Permutations, combinations, expected value, normal dist., regression

ACT Math 2 is an advanced subject-level mathematics course for students who have completed standard ACT Math preparation and wish to extend their skills into pre-calculus territory — the topics that appear in the hardest ACT questions and on ACT subject tests.

What to expect

This course covers the top-difficulty ACT Math topics: advanced algebra, pre-calculus functions, matrices, advanced trigonometry, and non-routine geometry. It is also ideal preparation for the ACT Subject Test in Mathematics, which tests material through pre-calculus.

Prerequisite
ACT Math (standard course)
Level
Pre-calculus and beyond
Ideal for
Score 28+ target students
Calculator
permitted throughout
⏱ ACT Subject Math 1 Pacing & Time Management Strategy

  • Pacing Baseline: 50 questions in 60 minutes = 72 seconds per question. There is no guessing penalty — every unanswered question is a lost opportunity.
  • Three-Pass Strategy: Pass 1 (Questions 1–25, ~20 min): bank easy points rapidly. Pass 2 (Questions 26–45, ~25 min): methodical solving of mid-level algebra, trig, and coordinate geometry. Pass 3 (Questions 46–50 & review, ~15 min): tackle non-routine multi-step items and ensure all bubble answers are filled.
  • Approved Calculator Fluency: Graphing calculators are permitted throughout. Store formulas, use matrix inverse/determinant functions, and verify complex number arithmetic a+bia + bi directly.

▲ The 4 Core Commandments for Scoring 30+ on ACT Advanced Math
  • 1. Never Leave Blanks: Unlike old SAT Subject tests, there is zero penalty for incorrect answers. If time is running short with 2 minutes remaining, pick a favorite letter (e.g., C or D) and fill every remaining bubble.
  • 2. Identify Conic Signatures at a Glance: In Ax2+Bxy+Cy2+Dx+Ey+F=0Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0, same signs on x2x^2 and y2y^2 with A=CA = C indicates a circle; same signs with A≠CA \neq C indicates an ellipse; opposite signs indicates a hyperbola; only one squared term indicates a parabola.
  • 3. Exploit Backsolving & Number Substitution: When an algebraic equation has complex fractions, logs, or radicals, testing answer choice C (the median value) first often eliminates 2–3 options in under 30 seconds.
  • 4. Memorize the Critical Edge-Case Formulas: Circle inscribed angle =12central=\frac{1}{2}\text{central}, Heron's formula A=s(s−a)(s−b)(s−c)A = \sqrt{s(s-a)(s-b)(s-c)}, sum of infinite geometric series S∞=a1−rS_\infty = \frac{a}{1-r}, and vector dot product u⃗⋅v⃗=u1v1+u2v2\vec{u}\cdot\vec{v} = u_1 v_1 + u_2 v_2.
Bar chart: ACT Math 2 Curriculum Distribution (%) with categories: Adv Algebra (15), Adv Functions (15), Pre-Calculus (12), Adv Trig (10), Coord Geometry (10), Plane Geometry (10), Stats & Prob (10), Number Theory (8)0481115Adv Algebra15Adv Functions15Pre-Calculus12Adv Trig10Coord Geometry10Plane Geometry10Stats & Prob10Number Theory8Approximate Percentage (%)ACT Math 2 Curriculum Distribution (%)
ACT Math 2 (Advanced Math) topic distribution across primary subject domains. Advanced Algebra, Functions, and Pre-Calculus comprise over 40% of the tested curriculum, supported by Advanced Trigonometry, Coordinate Geometry, and Plane Geometry.
The ACT Subject Test in Mathematics consists of 50 questions in 60 minutes. If a student spends an average of 55 seconds on each of the first 30 questions, how many seconds per question are available for the remaining 20 questions?
Time spent on first 30 questions=30×55=1650 seconds\text{Time spent on first 30 questions} = 30 \times 55 = 1650\text{ seconds} (27.5 minutes). Total time available=60×60=3600 seconds\text{Total time available} = 60 \times 60 = 3600\text{ seconds}. Remaining time=3600−1650=1950 seconds\text{Remaining time} = 3600 - 1650 = 1950\text{ seconds}. For the final 20 questions: 195020=97.5 seconds per question\frac{1950}{20} = 97.5\text{ seconds per question}.
📝 Chapter Quiz
1

Advanced Number Theory

🗻 Advanced Number Theory ~8%  ·  Integer properties  ·  Sequences & series  ·  Modular arithmetic  ·  Complex number operations

Number theory questions on hard ACT items test divisibility rules, prime factorisation, GCD and LCM, modular arithmetic, and properties of integers.

GCD
greatest common divisor
LCM
LCM(a,b)=abgcd⁡(a,b) \text{LCM}(a,b)=\dfrac{ab}{\gcd(a,b)}
Modular arithmetic
a≡r(modn) a \equiv r \pmod{n}
Prime factorisation
unique decomposition theorem
Number line from 0 to 30 with marked points0123456789101112131415161718192021222324252627282930a₁ = 5a₂ = 10a₃ = 15a₄ = 20a₅ = 25
Terms of an arithmetic progression on the number line with initial term a1=5 a_1 = 5 and common difference d=5 d = 5 . The sum of the first 5 terms is S5=52(5+25)=75 S_5 = \frac{5}{2}(5 + 25) = 75 .
Worked example 1.A

Find LCM(12, 18). 12=22⋅3,18=2⋅32.LCM=22⋅32=36. 12=2^2\cdot 3,\quad 18=2\cdot 3^2.\quad \text{LCM}=2^2\cdot 3^2=36.

Complex numbers revisited

On advanced ACT items, complex numbers appear in equation-solving contexts: x2+4=0⇒x=±2i x^2+4=0 \Rightarrow x=\pm 2i . The modulus of a+bi a+bi is a2+b2 \sqrt{a^2+b^2} .

● Sequences & Modular Arithmetic

An arithmetic sequence: an=a1+(n−1)da_n = a_1 + (n-1)d. A geometric sequence: an=a1rn−1a_n = a_1 r^{n-1}. Modular arithmetic: a≡b(modm)a \equiv b \pmod{m} means m∣(a−b)m \mid (a-b). Useful for finding last digits (mod 10) or remainders.

Worked example — Last digit of a power

What is the units digit of 720267^{2026}?

Powers of 7 cycle: 71=7,72=49,73=343,74=2401,75=…77^1=7, 7^2=49, 7^3=343, 7^4=2401, 7^5=\ldots7. Cycle length 4. 2026÷42026 \div 4 remainder 22. So units digit = same as 727^2 = 9.

▲ ACT Math 2 Traps & Pitfalls — Number Theory & Complex Numbers
  • Powers of ii Cycle Modulo 4: i1=ii^1 = i, i2=−1i^2 = -1, i3=−ii^3 = -i, and i4=1i^4 = 1. To evaluate iki^k, find k(mod4)k \pmod 4: remainder 1 gives ii, remainder 2 gives −1-1, remainder 3 gives −i-i, and remainder 0 gives 11.
  • Complex Fraction Rationalization: To simplify a+bic+di\dfrac{a+bi}{c+di}, multiply both numerator and denominator by the complex conjugate c−dic - di. The denominator becomes the real number c2+d2c^2 + d^2.
  • Infinite Geometric Series Convergence: The sum formula S∞=a11−rS_\infty = \dfrac{a_1}{1 - r} is strictly valid ONLY when ∣r∣<1|r| < 1. If ∣r∣≥1|r| \ge 1, the series diverges and has no finite sum.
  • GCD vs. LCM Relationship: Remember the product identity GCD(a,b)×LCM(a,b)=a×b\text{GCD}(a,b) \times \text{LCM}(a,b) = a \times b. If a question asks for the LCM given prime factorizations, take the highest power of each distinct prime; for GCD, take the lowest common power.
The sum of an arithmetic sequence is 150, with first term 5 and last term 25. How many terms are there?
S=n2(a1+an)=n2(30)=150⇒n=10S = \dfrac{n}{2}(a_1+a_n) = \dfrac{n}{2}(30) = 150 \Rightarrow n = 10.
Express the complex number z=5+2i3−4iz = \dfrac{5 + 2i}{3 - 4i} in standard form a+bia + bi, and determine its modulus ∣z∣|z|.

(a) Standard form a+bia + bi: Multiply numerator and denominator by the complex conjugate 3+4i3 + 4i: z=(5+2i)(3+4i)(3−4i)(3+4i)=15+20i+6i+8i232−(4i)2=15+26i−89−(−16)=7+26i25=725+2625i. z = \dfrac{(5 + 2i)(3 + 4i)}{(3 - 4i)(3 + 4i)} = \dfrac{15 + 20i + 6i + 8i^2}{3^2 - (4i)^2} = \dfrac{15 + 26i - 8}{9 - (-16)} = \dfrac{7 + 26i}{25} = \dfrac{7}{25} + \dfrac{26}{25}i.

(b) Modulus ∣z∣|z|: Using the modulus quotient property ∣z∣=∣5+2i∣∣3−4i∣|z| = \dfrac{|5+2i|}{|3-4i|}: ∣5+2i∣=52+22=29|5+2i| = \sqrt{5^2 + 2^2} = \sqrt{29}, and ∣3−4i∣=32+(−4)2=25=5|3-4i| = \sqrt{3^2 + (-4)^2} = \sqrt{25} = 5. Thus ∣z∣=295|z| = \dfrac{\sqrt{29}}{5} (or ≈1.077\approx 1.077).

📝 Chapter Quiz
2

Advanced Algebra & Systems

🗻 Advanced Algebra ~15%  ·  Polynomial systems  ·  Rational equations  ·  Logarithms & exponentials  ·  Absolute value in systems

Advanced ACT algebra includes matrices, non-linear systems, and applications of polynomial and rational functions.

Matrix addition
add corresponding entries
Matrix product AB AB
row × column dot products
2×2 determinant
ad−bc ad-bc
System via matrices
Ax=b A\mathbf{x}=\mathbf{b}
Worked example 2.A

Solve the non-linear system: y=x2 y=x^2 and y=x+2 y=x+2 . x2=x+2  ⟹  x2−x−2=0  ⟹  (x−2)(x+1)=0  ⟹  x=2 or x=−1. x^2=x+2 \implies x^2-x-2=0 \implies (x-2)(x+1)=0 \implies x=2 \text{ or } x=-1.

Non-Linear System Intersection: y = x² and y = x + 2 — Coordinate plane with graph of y = x², y = x + 2; marked points (-1, 1) (-1, 1), (2, 4) (2, 4)-2-1123246xyy = x²y = x + 2(-1, 1)(2, 4)y = 0
Graphical solution of the non-linear system y=x2 y = x^2 and y=x+2 y = x + 2 . The line intersects the upward parabola at precisely two coordinate points: (−1,1) (-1, 1) and (2,4) (2, 4) .
● Logarithms & Exponential Equations

Key log laws: log⁡b(xy)=log⁡bx+log⁡by\log_b(xy) = \log_b x + \log_b y; log⁡b(x/y)=log⁡bx−log⁡by\log_b(x/y) = \log_b x - \log_b y; log⁡b(xn)=nlog⁡bx\log_b(x^n) = n\log_b x. To solve af(x)=ba^{f(x)} = b: take log⁡\log of both sides. Change of base: log⁡bx=ln⁡xln⁡b\log_b x = \dfrac{\ln x}{\ln b}.

Worked example — Solving a logarithmic equation

Solve log⁡2(x+3)+log⁡2(x−1)=5\log_2(x+3) + \log_2(x-1) = 5.

log⁡2[(x+3)(x−1)]=5⇒(x+3)(x−1)=32⇒x2+2x−35=0⇒(x+7)(x−5)=0\log_2[(x+3)(x-1)] = 5 \Rightarrow (x+3)(x-1) = 32 \Rightarrow x^2+2x-35 = 0 \Rightarrow (x+7)(x-5) = 0.

x=5x = 5 (reject x=−7x=-7 since x−1>0x-1 > 0 required). Answer: x=5x=5.

▲ ACT Math 2 Traps & Pitfalls — Matrices & Advanced Systems
  • Matrix Multiplication Order & Dimensions: To compute ABAB, the number of columns in AA (inner dimension) must equal the number of rows in BB: (m×k)×(k×n)=(m×n)(m \times k) \times (k \times n) = (m \times n). Furthermore, AB≠BAAB \neq BA in general — matrix multiplication is non-commutative!
  • Determinant & Singularity: For A=(abcd)A = \begin{pmatrix} a & b \\ c & d \end{pmatrix}, det⁡(A)=ad−bc\det(A) = ad - bc. The matrix inverse A−1A^{-1} exists if and only if det⁡(A)≠0\det(A) \neq 0. If det⁡(A)=0\det(A) = 0, the corresponding linear system has either no unique solution (inconsistent or dependent).
  • Extraneous Solutions in Rational Equations: When clearing denominators by multiplying by a common multiple, values that make any original denominator equal to zero are extraneous and must be discarded.
  • Logarithm Bases & Power Properties: Remember log⁡b(A+B)≠log⁡bA+log⁡bB\log_b(A + B) \neq \log_b A + \log_b B. The addition rule applies only inside the logarithm: log⁡b(AB)=log⁡bA+log⁡bB\log_b(AB) = \log_b A + \log_b B.
Solve for xx: 3x+1=5x3^{x+1} = 5^x. Give your answer in terms of logarithms.
Take ln⁡\ln: (x+1)ln⁡3=xln⁡5⇒xln⁡3+ln⁡3=xln⁡5⇒x=ln⁡3ln⁡5−ln⁡3=ln⁡3ln⁡(5/3)(x+1)\ln 3 = x\ln 5 \Rightarrow x\ln 3 + \ln 3 = x\ln 5 \Rightarrow x = \dfrac{\ln 3}{\ln 5 - \ln 3} = \dfrac{\ln 3}{\ln(5/3)}.
Let matrices A=(3−124)A = \begin{pmatrix} 3 & -1 \\ 2 & 4 \end{pmatrix} and B=(150−2)B = \begin{pmatrix} 1 & 5 \\ 0 & -2 \end{pmatrix}. (a) Compute the matrix product ABAB. (b) Calculate det⁡(A)\det(A), det⁡(B)\det(B), and verify that det⁡(AB)=det⁡(A)det⁡(B)\det(AB) = \det(A)\det(B).

(a) Matrix product ABAB: AB=((3)(1)+(−1)(0)(3)(5)+(−1)(−2)(2)(1)+(4)(0)(2)(5)+(4)(−2))=(315+2210−8)=(31722). AB = \begin{pmatrix} (3)(1) + (-1)(0) & (3)(5) + (-1)(-2) \\ (2)(1) + (4)(0) & (2)(5) + (4)(-2) \end{pmatrix} = \begin{pmatrix} 3 & 15 + 2 \\ 2 & 10 - 8 \end{pmatrix} = \begin{pmatrix} 3 & 17 \\ 2 & 2 \end{pmatrix}.

(b) Determinant calculation: det⁡(A)=(3)(4)−(−1)(2)=12+2=14\det(A) = (3)(4) - (-1)(2) = 12 + 2 = 14. det⁡(B)=(1)(−2)−(5)(0)=−2\det(B) = (1)(-2) - (5)(0) = -2. Then det⁡(A)det⁡(B)=14(−2)=−28\det(A)\det(B) = 14(-2) = -28. From the product: det⁡(AB)=(3)(2)−(17)(2)=6−34=−28\det(AB) = (3)(2) - (17)(2) = 6 - 34 = -28. Thus det⁡(AB)=det⁡(A)det⁡(B)=−28\det(AB) = \det(A)\det(B) = -28. ✓\checkmark

📝 Chapter Quiz
3

Advanced Functions

🗻 Advanced Functions ~15%  ·  Piecewise & recursive  ·  Parametric  ·  Composition chains  ·  Inverse functions

Pre-calculus functions — rational, piecewise, exponential, and logarithmic — with composition, inverses, and detailed graph analysis.

Rational function
P(x)Q(x) \dfrac{P(x)}{Q(x)} — vertical asymptotes where Q=0Q=0
Horizontal asymptote
compare degrees of P P and Q Q
Piecewise
different rules on different intervals
Even / odd
f(−x)=f(x) f(-x)=f(x) / f(−x)=−f(x) f(-x)=-f(x)
Worked example 3.A

Find the horizontal asymptote of f(x)=3x2+1x2−4 f(x)=\dfrac{3x^2+1}{x^2-4} .

Both numerator and denominator have degree 2; ratio of leading coefficients: y=31=3 y=\dfrac{3}{1}=3 .

⊙ Explorer · Rational function asymptotesinteractive
vertical asymptotex = 1
horizontal asymptotey = 0

f(x)=2x−p+qf(x)=\dfrac{2}{x-p}+q — the denominator vanishing at x=px=p makes the vertical asymptote; as x→±∞x\to\pm\infty, f(x)→qf(x)\to q.

● Piecewise & Recursive Functions

A piecewise function uses different rules for different intervals. A recursive function is defined by its previous terms: e.g. a1=2a_1 = 2, an=3an−1−1a_n = 3a_{n-1} - 1. Parametric equations express xx and yy as separate functions of a parameter tt.

Worked example — Parametric to Cartesian

Eliminate tt from x=t+2x = t+2, y=t2−1y = t^2 - 1.

From x=t+2x = t+2: t=x−2t = x-2. Substitute: y=(x−2)2−1=x2−4x+3y = (x-2)^2 - 1 = x^2 - 4x + 3. Parabola.

Rational Function: f(x) = (2x - 1)/(x - 2) — Coordinate plane with graph of f(x) = (2x-1)/(x-2); marked points (0, 0.5) (0, 0.5), (3, 5) (3, 5), (1, -1) (1, -1)-2-1123456-4-2246xyf(x) = (2x-1)/(x-2)(0, 0.5)(3, 5)(1, -1)HA: y = 2
Graph of the rational function f(x)=2x−1x−2 f(x) = \dfrac{2x - 1}{x - 2} . The denominator zero produces the vertical asymptote x=2 x = 2 , while the ratio of equal leading coefficients produces the horizontal asymptote y=2 y = 2 .
▲ ACT Math 2 Traps & Pitfalls — Rational, Piecewise & Inverse Functions
  • Holes vs. Vertical Asymptotes: If a factor cancels from both numerator and denominator, it creates a removable hole (c,y0)(c, y_0), NOT a vertical asymptote. A vertical asymptote occurs ONLY where the reduced denominator equals zero.
  • Piecewise Boundary Conditions: When evaluating piecewise functions at domain boundaries (e.g. x=0x = 0), check the inequality symbols carefully (<< vs. ≤\le) to apply the correct rule.
  • Inverse Function Domain & Range Swap: The domain of f−1f^{-1} is the range of ff, and the range of f−1f^{-1} is the domain of ff. A function only has an inverse function if it is strictly one-to-one (passes the horizontal line test).
  • Composite Function Order: (f∘g)(x)=f(g(x))(f \circ g)(x) = f(g(x)) means evaluate g(x)g(x) first, then substitute that output into ff. In general, f(g(x))≠g(f(x))f(g(x)) \neq g(f(x)).
A function is defined piecewise: f(x)=x2f(x) = x^2 for x<0x < 0, and f(x)=2x+1f(x) = 2x+1 for x≥0x \geq 0. Find f(−3)+f(2)f(-3) + f(2).
f(−3)=(−3)2=9f(-3) = (-3)^2 = 9. f(2)=2(2)+1=5f(2) = 2(2)+1 = 5. Sum =14= 14.
Let f(x)=3x+4x−2f(x) = \dfrac{3x + 4}{x - 2} for x≠2x \neq 2. (a) Determine the equations of all vertical and horizontal asymptotes of f(x)f(x). (b) Derive the inverse function formula f−1(x)f^{-1}(x).

(a) Asymptotes: Vertical asymptote: denominator zero x−2=0⇒x=2x - 2 = 0 \Rightarrow x = 2. Horizontal asymptote: degrees of numerator and denominator are both 1, so y=31=3y = \dfrac{3}{1} = 3.

(b) Inverse function: Set y=3x+4x−2y = \dfrac{3x + 4}{x - 2}. Solve for xx: y(x−2)=3x+4  ⟹  xy−2y=3x+4  ⟹  xy−3x=2y+4  ⟹  x(y−3)=2y+4. y(x - 2) = 3x + 4 \implies xy - 2y = 3x + 4 \implies xy - 3x = 2y + 4 \implies x(y - 3) = 2y + 4. Thus x=2y+4y−3x = \dfrac{2y + 4}{y - 3}. Swapping variables: f−1(x)=2x+4x−3f^{-1}(x) = \dfrac{2x + 4}{x - 3} for x≠3x \neq 3.

📝 Chapter Quiz
4

Advanced Trigonometry

🗻 Advanced Trigonometry ~10%  ·  Radians & unit circle  ·  Trig identities  ·  Law of sines/cosines  ·  Inverse trig

Beyond SOHCAHTOA — the unit circle, inverse trig functions, sum/difference identities, and solving trig equations over a given interval.

Sum formula sin
sin⁡(A+B)=sin⁡Acos⁡B+cos⁡Asin⁡B \sin(A+B)=\sin A\cos B+\cos A\sin B
Sum formula cos
cos⁡(A+B)=cos⁡Acos⁡B−sin⁡Asin⁡B \cos(A+B)=\cos A\cos B-\sin A\sin B
Law of sines
asin⁡A=bsin⁡B \dfrac{a}{\sin A}=\dfrac{b}{\sin B}
Inverse trig
sin⁡−1,cos⁡−1,tan⁡−1 \sin^{-1},\cos^{-1},\tan^{-1}
Worked example 4.A

Find all solutions to 2sin⁡θ−1=0 2\sin\theta-1=0 on [0,2π) [0,2\pi) . sin⁡θ=12  ⟹  θ=π6 or θ=5π6. \sin\theta=\tfrac{1}{2} \implies \theta=\tfrac{\pi}{6} \text{ or } \theta=\tfrac{5\pi}{6}.

⊙ Explorer · Law of Cosinesinteractive
c² = a² + b² − 2ab cos C8.89
● Law of Sines, Cosines & Identities

Law of Sines: asin⁡A=bsin⁡B=csin⁡C\dfrac{a}{\sin A} = \dfrac{b}{\sin B} = \dfrac{c}{\sin C}. Law of Cosines: c2=a2+b2−2abcos⁡Cc^2 = a^2+b^2-2ab\cos C. Key identities: sin⁡2θ+cos⁡2θ=1\sin^2\theta+\cos^2\theta=1; sin⁡2θ=2sin⁡θcos⁡θ\sin 2\theta = 2\sin\theta\cos\theta; cos⁡2θ=cos⁡2θ−sin⁡2θ\cos 2\theta = \cos^2\theta - \sin^2\theta.

Worked example — Law of Cosines

A triangle has sides a=7,b=10a=7, b=10 and included angle C=60°C=60°. Find side cc.

c2=49+100−2(7)(10)cos⁡60°=149−70=79c^2 = 49 + 100 - 2(7)(10)\cos 60° = 149 - 70 = 79. c=79≈8.89c = \sqrt{79} \approx 8.89.

Unit circle diagram showing terminal angle 120: Unit Circle: Special Angle 120° (2π/3 rad)Unit Circle: Special Angle 120° (2π/3 rad)xy120°(-0.5, 0.866)
Unit circle coordinates for θ=120∘=2π3 rad \theta = 120^\circ = \frac{2\pi}{3}\text{ rad} . The terminal point has coordinates (cos⁡120∘,sin⁡120∘)=(−12,32) (\cos 120^\circ, \sin 120^\circ) = \left(-\frac{1}{2}, \frac{\sqrt{3}}{2}\right) with reference angle 60∘ 60^\circ in Quadrant II.
▲ ACT Math 2 Traps & Pitfalls — Trigonometry & Angle Measures
  • Radian vs. Degree Calculator Mode: ACT questions mix degrees (e.g. 120°120°) and radians (e.g. 2π/32\pi/3). Check your calculator mode before every trig calculation! If you get unexpected decimals for standard values, check the mode first.
  • Signs by Quadrant (ASTC): In Quadrant II, sine is positive but cosine and tangent are negative. In Quadrant III, tangent is positive but sine and cosine are negative. In Quadrant IV, cosine is positive but sine and tangent are negative.
  • The Ambiguous Case (SSA): When using the Law of Sines with two sides and an opposite angle (SSA), always check whether the supplementary angle 180°−B180° - B can form a valid second triangle (sum of angles < 180°).
  • Double-Angle Cosine Forms: Remember the three equivalent forms: cos⁡(2θ)=cos⁡2θ−sin⁡2θ=2cos⁡2θ−1=1−2sin⁡2θ\cos(2\theta) = \cos^2\theta - \sin^2\theta = 2\cos^2\theta - 1 = 1 - 2\sin^2\theta. Choosing the form matching the other terms simplifies quadratic trig equations immediately.
Prove that 1−cos⁡2θsin⁡2θ=tan⁡θ\dfrac{1-\cos 2\theta}{\sin 2\theta} = \tan\theta.
1−(1−2sin⁡2θ)2sin⁡θcos⁡θ=2sin⁡2θ2sin⁡θcos⁡θ=sin⁡θcos⁡θ=tan⁡θ\dfrac{1-(1-2\sin^2\theta)}{2\sin\theta\cos\theta} = \dfrac{2\sin^2\theta}{2\sin\theta\cos\theta} = \dfrac{\sin\theta}{\cos\theta} = \tan\theta. ✓
Solve the quadratic trigonometric equation 2sin⁡2θ−3sin⁡θ+1=02\sin^2\theta - 3\sin\theta + 1 = 0 for all solutions θ∈[0,2π)\theta \in [0, 2\pi).

Factoring: Factor as a quadratic in sin⁡θ\sin\theta: (2sin⁡θ−1)(sin⁡θ−1)=0. (2\sin\theta - 1)(\sin\theta - 1) = 0.

Case 1: 2sin⁡θ−1=0  ⟹  sin⁡θ=122\sin\theta - 1 = 0 \implies \sin\theta = \dfrac{1}{2}. In [0,2π)[0, 2\pi), sine is positive in Quadrants I and II with reference angle π/6\pi/6: θ=π6,θ=π−π6=5π6. \theta = \dfrac{\pi}{6},\quad \theta = \pi - \dfrac{\pi}{6} = \dfrac{5\pi}{6}.

Case 2: sin⁡θ−1=0  ⟹  sin⁡θ=1\sin\theta - 1 = 0 \implies \sin\theta = 1. In [0,2π)[0, 2\pi), sine equals 1 at θ=π2\theta = \dfrac{\pi}{2}.

Complete solution set: {π6, π2, 5π6}\left\{ \dfrac{\pi}{6},\, \dfrac{\pi}{2},\, \dfrac{5\pi}{6} \right\}.

📝 Chapter Quiz
5

Pre-Calculus Concepts

🗻 Pre-Calculus Concepts ~12%  ·  Limits (informal)  ·  Sequences & series  ·  Conic sections  ·  Polar coordinates

Limits, sequences, series, and polynomial behaviour give students the conceptual scaffolding for calculus — and appear on the hardest ACT questions.

Limit intuition
lim⁡x→af(x) \lim_{x\to a}f(x) — value f f approaches
Geometric series
a11−r, ∣r∣<1 \dfrac{a_1}{1-r},\ |r|<1
Binomial theorem
(a+b)n=∑(nk)an−kbk (a+b)^n=\sum\binom{n}{k}a^{n-k}b^k
Parametric
x=f(t), y=g(t) x=f(t),\ y=g(t)
Worked example 5.A

Evaluate ∑n=1∞3(12)n−1 \displaystyle\sum_{n=1}^{\infty}3\left(\tfrac{1}{2}\right)^{n-1} . S=31−12=312=6. S=\frac{3}{1-\tfrac{1}{2}}=\frac{3}{\tfrac{1}{2}}=6.

● Limits & Conic Sections

Informal limit: lim⁡x→af(x)=L\lim_{x \to a}f(x) = L means f(x)f(x) approaches LL as xx approaches aa. Conic sections — standard forms: circle (x−h)2+(y−k)2=r2(x-h)^2+(y-k)^2=r^2; ellipse x2a2+y2b2=1\dfrac{x^2}{a^2}+\dfrac{y^2}{b^2}=1; hyperbola x2a2−y2b2=1\dfrac{x^2}{a^2}-\dfrac{y^2}{b^2}=1; parabola y=ax2+bx+cy=ax^2+bx+c.

Worked example — Identify and graph a conic

Identify the conic: 4x2+9y2=364x^2 + 9y^2 = 36.

Divide by 36: x29+y24=1\dfrac{x^2}{9}+\dfrac{y^2}{4}=1. This is an ellipse with a=3a=3 along xx-axis and b=2b=2 along yy-axis, centre (0,0)(0,0).

Conic Section: Ellipse x²/9 + y²/4 = 1 — Coordinate plane with graph of Top half, Bottom half; marked points (3, 0) (3, 0), (-3, 0) (-3, 0), (0, 2) (0, 2), (0, -2) (0, -2)-3-2-1123-2-112xyTop halfBottom half(3, 0)(-3, 0)(0, 2)(0, -2)
Standard ellipse x29+y24=1 \dfrac{x^2}{9} + \dfrac{y^2}{4} = 1 centered at (0,0) (0,0) . The major horizontal axis has length 2a=6 2a = 6 (vertices (±3,0) (\pm 3, 0) ) and the minor vertical axis has length 2b=4 2b = 4 (co-vertices (0,±2) (0, \pm 2) ).
▲ ACT Math 2 Traps & Pitfalls — Limits, Conics & Binomial Expansion
  • Indeterminate Form 0/00/0 vs. Undefined: When direct substitution into lim⁡x→af(x)g(x)\lim_{x \to a} \dfrac{f(x)}{g(x)} yields 0/00/0, the limit is indeterminate — factor and cancel the common factor (x−a)(x - a) before re-evaluating. Do NOT write 'undefined' or 'does not exist'!
  • Focal Distance in Ellipses vs. Hyperbolas: For an ellipse, the focal distance satisfies c2=a2−b2c^2 = a^2 - b^2 (where a>ba > b). For a hyperbola, the focal distance satisfies c2=a2+b2c^2 = a^2 + b^2. Confusing these two relation signs is one of the most common mistakes on ACT Math 2.
  • The kk-th Term Index in Binomial Expansion: In the expansion of (a+b)n(a+b)^n, the general term is Tk+1=(nk)an−kbkT_{k+1} = \binom{n}{k} a^{n-k} b^k. The 4th term corresponds to index k=3k = 3, not k=4k = 4! Watch negative signs when expanding expressions like (2x−3)n(2x - 3)^n.
  • Infinite Series Ratio Magnitude: For ∑a1rn−1\sum a_1 r^{n-1}, if ∣r∣≥1|r| \ge 1, the series does not converge, so applying S=a11−rS = \dfrac{a_1}{1-r} produces a false number.
Find lim⁡x→3x2−9x−3\lim_{x \to 3}\dfrac{x^2-9}{x-3}.
Factor: (x−3)(x+3)x−3=x+3\dfrac{(x-3)(x+3)}{x-3} = x+3. As x→3x \to 3: limit =6= 6.
Find the 4th term in the binomial expansion of (2x−3)6(2x - 3)^6.

Using the binomial theorem general term formula Tk+1=(nk)an−kbkT_{k+1} = \binom{n}{k} a^{n-k} b^k with n=6n = 6, a=2xa = 2x, b=−3b = -3, and k=3k = 3 (for the 4th term): T4=(63)(2x)6−3(−3)3. T_4 = \binom{6}{3} (2x)^{6-3} (-3)^3. Compute the binomial coefficient: (63)=6×5×43×2×1=20\binom{6}{3} = \dfrac{6 \times 5 \times 4}{3 \times 2 \times 1} = 20. T4=20⋅(2x)3⋅(−27)=20⋅(8x3)⋅(−27)=−4320x3. T_4 = 20 \cdot (2x)^3 \cdot (-27) = 20 \cdot (8x^3) \cdot (-27) = -4320x^3.

📝 Chapter Quiz
6

Advanced Coordinate Geometry

🗻 Advanced Coordinate Geometry ~10%  ·  Conic equations  ·  Rotations & transformations  ·  Distance in 3D  ·  Locus of points

Conics in standard and general form, transformations, and polar coordinates are tested on advanced ACT and ACT subject items.

Parabola (vertical)
(x−h)2=4p(y−k) (x-h)^2=4p(y-k)
Ellipse
x2a2+y2b2=1 \dfrac{x^2}{a^2}+\dfrac{y^2}{b^2}=1
Hyperbola
x2a2−y2b2=1 \dfrac{x^2}{a^2}-\dfrac{y^2}{b^2}=1
Polar
x=rcos⁡θ, y=rsin⁡θ x=r\cos\theta,\ y=r\sin\theta
Worked example 6.A

Convert the polar point (4,π3) \left(4,\dfrac{\pi}{3}\right) to Cartesian. x=4cos⁡π3=4⋅12=2,y=4sin⁡π3=4⋅32=23. x=4\cos\tfrac{\pi}{3}=4\cdot\tfrac{1}{2}=2,\quad y=4\sin\tfrac{\pi}{3}=4\cdot\tfrac{\sqrt3}{2}=2\sqrt3.

● Conics in Standard Form & 3D Distance

Completing the square converts a general conic to standard form. 3D distance: d=(x2−x1)2+(y2−y1)2+(z2−z1)2d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2+(z_2-z_1)^2}. A rotation of axes by θ\theta transforms x=Xcos⁡θ−Ysin⁡θx = X\cos\theta - Y\sin\theta, y=Xsin⁡θ+Ycos⁡θy = X\sin\theta + Y\cos\theta.

Worked example — Complete the square to find a circle

Write x2+y2−6x+4y−3=0x^2+y^2-6x+4y-3=0 in standard form.

(x2−6x+9)+(y2+4y+4)=3+9+4=16(x^2-6x+9)+(y^2+4y+4) = 3+9+4 = 16. Centre (3,−2)(3,-2), radius 44.

Circle in Coordinate Plane: (x - 3)² + (y + 2)² = 16 — Coordinate plane with graph of Top half, Bottom half; marked points Center (3, -2) (3, -2), (7, -2) (7, -2), (3, 2) (3, 2)-11234567-6-4-22xyTop halfBottom halfCenter (3, -2)(7, -2)(3, 2)y = −2
The circle (x−3)2+(y+2)2=16 (x - 3)^2 + (y + 2)^2 = 16 plotted on the Cartesian plane. The center is located at (h,k)=(3,−2) (h, k) = (3, -2) and the radius is r=16=4 r = \sqrt{16} = 4 .
▲ ACT Math 2 Traps & Pitfalls — Coordinate Geometry & 3D Space
  • Center Signs & Radius in Circle Equations: In (x−h)2+(y−k)2=r2(x - h)^2 + (y - k)^2 = r^2, the center is (h,k)(h, k). Watch the signs carefully: (x−3)2+(y+2)2=16(x - 3)^2 + (y + 2)^2 = 16 has center (3,−2)(3, -2), NOT (−3,2)(-3, 2), and its radius is 16=4\sqrt{16} = 4, NOT 16.
  • Perpendicular Slopes: Two lines are perpendicular if and only if their slopes are negative reciprocals: m⊥=−1/mm_\perp = -1/m. A common pitfall is forgetting the negative sign and taking merely the reciprocal.
  • Standard 2D Rotations About the Origin: A counterclockwise rotation of 90°90° maps (x,y)→(−y,x)(x, y) \to (-y, x); 180°180° maps (x,y)→(−x,−y)(x, y) \to (-x, -y); and 270°270° (or 90°90° clockwise) maps (x,y)→(y,−x)(x, y) \to (y, -x).
  • 3D Distance Extension: Do not collapse 3D distance into 2D: d=(x2−x1)2+(y2−y1)2+(z2−z1)2d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2 + (z_2 - z_1)^2}. All three coordinate differences must be squared.
Find the distance between points A(1,2,3)A(1,2,3) and B(4,6,3)B(4,6,3).
d=(4−1)2+(6−2)2+(3−3)2=9+16+0=25=5d = \sqrt{(4-1)^2+(6-2)^2+(3-3)^2} = \sqrt{9+16+0} = \sqrt{25} = 5.
Find the standard equation Ax+By=CAx + By = C of the line perpendicular to 3x−4y=123x - 4y = 12 that passes through the midpoint of the line segment joining P(−2,7)P(-2, 7) and Q(6,1)Q(6, 1).

(a) Midpoint MM: M=(−2+62,7+12)=(42,82)=(2,4). M = \left( \dfrac{-2 + 6}{2}, \dfrac{7 + 1}{2} \right) = \left( \dfrac{4}{2}, \dfrac{8}{2} \right) = (2, 4).

(b) Perpendicular slope: Rewrite the given line in slope-intercept form: 4y=3x−12⇒y=34x−34y = 3x - 12 \Rightarrow y = \dfrac{3}{4}x - 3. The slope is m=34m = \dfrac{3}{4}. The perpendicular slope is the negative reciprocal: m⊥=−43m_\perp = -\dfrac{4}{3}.

(c) Line equation: Using point-slope form with point (2,4)(2, 4): y−4=−43(x−2)  ⟹  3(y−4)=−4(x−2)  ⟹  3y−12=−4x+8  ⟹  4x+3y=20. y - 4 = -\dfrac{4}{3}(x - 2) \implies 3(y - 4) = -4(x - 2) \implies 3y - 12 = -4x + 8 \implies 4x + 3y = 20.

📝 Chapter Quiz
7

Advanced Plane Geometry

🗻 Advanced Plane Geometry ~10%  ·  Circle theorems  ·  Similarity & congruence proofs  ·  3D solids  ·  Geometric inequalities

Non-routine geometry questions involve multiple theorems applied together — circle inscribed in a triangle, overlapping regions, and proof-based reasoning.

Inscribed angle
12× \tfrac{1}{2}\times central angle
Power of a point
PA⋅PB=PC⋅PD PA\cdot PB=PC\cdot PD
Heron's formula
s(s−a)(s−b)(s−c) \sqrt{s(s-a)(s-b)(s-c)}
Regular polygon area
14ns2cot⁡(π/n) \tfrac{1}{4}ns^2\cot(\pi/n)
Worked example 7.A

Find the area of a triangle with sides 7, 8, 9. s=12,A=12⋅5⋅4⋅3=720=125. s=12,\quad A=\sqrt{12\cdot5\cdot4\cdot3}=\sqrt{720}=12\sqrt5.

⊙ Explorer · Inscribed angle theoreminteractive
central angle ∠AOB140.0°
inscribed angle ∠ACB70.0°

C sits anywhere on the major arc — drag the slider and the inscribed angle stays exactly half the central angle, every time.

● Circle Theorems & 3D Solids

Key circle theorems: (1) Angle at centre = 2 × angle at circumference. (2) Angles in same segment are equal. (3) Opposite angles in cyclic quadrilateral sum to 180°. (4) Tangent ⊥ radius. Surface area of sphere: 4πr24\pi r^2; volume: 43πr3\dfrac{4}{3}\pi r^3. Cone volume: 13πr2h\dfrac{1}{3}\pi r^2 h.

Worked example — Circle theorem

O is the centre of a circle. Angle AOB=140°AOB = 140°. Find the angle ACBACB where CC is on the major arc.

Angle at circumference on minor arc =140°/2=70°= 140°/2 = 70°. CC is on major arc, so ∠ACB=180°−70°=110°\angle ACB = 180° - 70° = 110° (opposite angles in cyclic quad sum to 180°180°).

Scalene Triangle for Heron's Formula — Triangle ABC with sides 9, 8, 7ABC987
Scalene triangle with side lengths a=7 a = 7 , b=8 b = 8 , and c=9 c = 9 . Using Heron's formula with semi-perimeter s=12 s = 12 , the area is A=12(5)(4)(3)=125≈26.83 A = \sqrt{12(5)(4)(3)} = 12\sqrt{5} \approx 26.83 .
▲ ACT Math 2 Traps & Pitfalls — Circle Theorems & 3D Geometry
  • Inscribed Angle vs. Central Angle: The inscribed angle ∠ACB\angle ACB subtended by an arc is exactly half the central angle ∠AOB\angle AOB: ∠ACB=12∠AOB\angle ACB = \frac{1}{2} \angle AOB. Inscribed angles subtending the same chord from opposite sides of the circle are supplementary, not equal!
  • Cyclic Quadrilateral Angles: A quadrilateral is cyclic (inscribed in a circle) if and only if opposite angles sum to 180°180°: ∠A+∠C=180°\angle A + \angle C = 180° and ∠B+∠D=180°\angle B + \angle D = 180°.
  • Vertical Height vs. Slant Height in 3D Solids: In cones and pyramids, the volume formula V=13BhV = \frac{1}{3}Bh uses the perpendicular vertical height hh, NOT the slant height ll. Use the Pythagorean theorem l2=r2+h2l^2 = r^2 + h^2 to solve for hh first!
  • Tangent-Secant Power of a Point: If a tangent segment PTPT and a secant line PABPAB are drawn from an external point PP, the power of a point theorem states PT2=PA⋅PBPT^2 = PA \cdot PB, where PBPB is the entire external secant length.
A cone has base radius 6 cm and slant height 10 cm. Find its total surface area.
Height: h=100−36=8h = \sqrt{100-36} = 8 cm. TSA =πr2+πrl=36π+60π=96π≈301.6= \pi r^2 + \pi r l = 36\pi + 60\pi = 96\pi \approx 301.6 cm2^2.
A quadrilateral ABCDABCD is inscribed in a circle. If ∠DAB=(2x+15)∘\angle DAB = (2x + 15)^\circ and the opposite angle ∠DCB=(3x−10)∘\angle DCB = (3x - 10)^\circ, determine the value of xx and calculate the measure of ∠DAB\angle DAB.

(a) Supplementary property: Opposite angles of any cyclic quadrilateral sum to 180∘180^\circ: (2x+15)+(3x−10)=180  ⟹  5x+5=180  ⟹  5x=175  ⟹  x=35. (2x + 15) + (3x - 10) = 180 \implies 5x + 5 = 180 \implies 5x = 175 \implies x = 35.

(b) Angle measure: Substitute x=35x = 35 into ∠DAB\angle DAB: ∠DAB=2(35)+15=70+15=85∘. \angle DAB = 2(35) + 15 = 70 + 15 = 85^\circ. (Check: ∠DCB=3(35)−10=105−10=95∘\angle DCB = 3(35) - 10 = 105 - 10 = 95^\circ, and 85∘+95∘=180∘85^\circ + 95^\circ = 180^\circ).

📝 Chapter Quiz
8

Statistics, Counting & Probability

🗻 Statistics, Counting & Probability ~10%  ·  Permutations & combinations  ·  Expected value  ·  Normal distribution  ·  Regression & residuals

Advanced ACT Math includes combinations, permutations, compound probability, and normal distribution concepts.

Permutations
nPr=n!(n−r)! _nP_r=\dfrac{n!}{(n-r)!}
Combinations
(nr)=n!r!(n−r)! \binom{n}{r}=\dfrac{n!}{r!(n-r)!}
Bayes (simple)
P(A∣B)=P(B∣A)P(A)P(B) P(A|B)=\dfrac{P(B|A)P(A)}{P(B)}
Expected value
E=∑xiP(xi) E=\sum x_i P(x_i)
Worked example 8.A

How many 3-letter arrangements (order matters) can be made from the word MATH? 4P3=4!1!=24. _4P_3=\frac{4!}{1!}=24.

● Counting, Expected Value & Normal Distribution

Fundamental counting principle: m×nm \times n ways for two independent events. Expected value: E(X)=∑xiP(xi)E(X) = \sum x_i P(x_i). Standard normal: z=x−μσz = \dfrac{x-\mu}{\sigma}; about 68% of data within 1σ1\sigma, 95% within 2σ2\sigma, 99.7% within 3σ3\sigma.

Worked example — Expected value

A game pays $8 if you roll a 6 on a fair die, and you lose $2 otherwise. What is the expected gain per roll?

E=8⋅16+(−2)⋅56=8−106=−26≈−$0.33E = 8 \cdot \dfrac{1}{6} + (-2) \cdot \dfrac{5}{6} = \dfrac{8-10}{6} = -\dfrac{2}{6} \approx -\$0.33.

The game is unfair — you lose on average 33 cents per roll.

Normal distribution bell curve (mean 100, sd 15): Normal Distribution: Empirical Rule 68–95–99.7% showing shaded probability regionNormal Distribution: Empirical Rule 68–95–99.7%557085100115130145
Normal distribution model with mean μ=100 \mu = 100 and standard deviation σ=15 \sigma = 15 . The shaded region represents the interval [μ−σ,μ+σ]=[85,115] [\mu - \sigma, \mu + \sigma] = [85, 115] , capturing approximately 68.2% 68.2\% of the distribution.
▲ ACT Math 2 Traps & Pitfalls — Probability, Counting & Normal Curves
  • Permutations vs. Combinations: Ask: 'Does order matter?' If order matters (ranking, electing distinct officers, line arrangements), use permutations nPr_nP_r. If group membership is all that counts (committees, picking toppings, drawing cards), use combinations (nr)\binom{n}{r}.
  • The Complement Shortcut for 'At Least One': Questions asking for the probability of 'at least one' of an event occurring are almost always solved fastest using the complement: P(at least one)=1−P(none)P(\text{at least one}) = 1 - P(\text{none}).
  • Signs in Expected Value: Losses, entry fees, or payouts must include their respective positive or negative signs in E=∑xiP(xi)E = \sum x_i P(x_i). If a ticket costs $5\$5 with a prize of $20\$20, the net gain when winning is +$15+\$15, not $20\$20.
  • Empirical Rule Sub-Intervals: Between the mean and +1σ+1\sigma lies 34%34\%; between +1σ+1\sigma and +2σ+2\sigma lies 13.5%13.5\%; between +2σ+2\sigma and +3σ+3\sigma lies 2.35%2.35\%; and above +3σ+3\sigma lies approximately 0.15%0.15\%.
In a class of 30, 18 play football (F), 14 play basketball (B), and 6 play both. How many play neither sport?
∣F∪B∣=18+14−6=26|F \cup B| = 18+14-6 = 26. Neither =30−26=4= 30-26 = 4.
A school committee of 4 members is to be selected from a club consisting of 6 juniors and 5 seniors. (a) In how many total ways can the 4 members be selected? (b) In how many ways can the committee be formed if it must contain exactly 2 juniors and 2 seniors?

(a) Unrestricted selection: Total students =6+5=11= 6 + 5 = 11. Choosing 4 where order does not matter: (114)=11×10×9×84×3×2×1=11×10×3=330 ways. \binom{11}{4} = \dfrac{11 \times 10 \times 9 \times 8}{4 \times 3 \times 2 \times 1} = 11 \times 10 \times 3 = 330 \text{ ways}.

(b) Exactly 2 juniors and 2 seniors: Select 2 juniors from 6, AND 2 seniors from 5: (62)×(52)=(6×52)×(5×42)=15×10=150 ways. \binom{6}{2} \times \binom{5}{2} = \left( \dfrac{6 \times 5}{2} \right) \times \left( \dfrac{5 \times 4}{2} \right) = 15 \times 10 = 150 \text{ ways}.

📝 Chapter Quiz
§

Practice set

Fifty advanced ACT Math problems — pre-algebra and number theory, advanced algebra, functions, trigonometry, coordinate geometry, plane geometry, and statistics — all graded by difficulty.

1

Simplify 4!2!⋅2! \dfrac{4!}{2!\cdot2!} .

Basic
242×2=6. \dfrac{24}{2\times2}=6.
2

Find gcd⁡(48, 36) \gcd(48,\,36) .

Basic
gcd⁡(48,36)=12. \gcd(48,36)=12.
3

Express 0.27‾ 0.\overline{27} as a fraction.

Intermediate

Let x=0.27‾ x=0.\overline{27} . Then 100x=27.27‾ 100x=27.\overline{27} , so 99x=27 99x=27 .

x=2799=311. x=\dfrac{27}{99}=\dfrac{3}{11}.
4

A 12% 12\% annual interest rate is applied to 5000. Find the amount after 2 years with compound interest.

Intermediate
A=5000(1.12)2=5000×1.2544=6272. A=5000(1.12)^2=5000\times1.2544=6272.
5

Find the LCM of 12 and 18.

Basic
LCM(12,18)=36. \text{LCM}(12,18)=36.
6

Solve 3x2−5x−2=0 3x^2 - 5x - 2 = 0 .

Intermediate
(3x+1)(x−2)=0⇒x=2 or x=−13. (3x+1)(x-2)=0 \Rightarrow x=2\text{ or }x=-\tfrac{1}{3}.
7

For what values of k k does x2−kx+9=0 x^2-kx+9=0 have equal roots?

Advanced

Discriminant =k2−36=0 =k^2-36=0 .

k=±6. k=\pm6.
8

Simplify x2−x−6x2−4 \dfrac{x^2-x-6}{x^2-4} .

Intermediate
(x−3)(x+2)(x−2)(x+2)=x−3x−2. \dfrac{(x-3)(x+2)}{(x-2)(x+2)}=\dfrac{x-3}{x-2}.
9

Solve x+6−x=1 \sqrt{x+6}-\sqrt{x}=1 .

Advanced

Square both sides after isolating: x+6=x+2x+1⇒5=2x⇒x=254 x+6=x+2\sqrt{x}+1 \Rightarrow 5=2\sqrt{x} \Rightarrow x=\tfrac{25}{4} .

10

Solve the system: x2−y=3 x^2-y=3 and x+y=1 x+y=1 .

Advanced

y=1−x y=1-x . Then x2−1+x=3⇒x2+x−4=0⇒x=−1±172 x^2-1+x=3\Rightarrow x^2+x-4=0 \Rightarrow x=\dfrac{-1\pm\sqrt{17}}{2} .

11

If f(x)=∣2x−3∣ f(x)=|2x-3| , find f(−1) f(-1) .

Basic
∣2(−1)−3∣=∣−5∣=5. |2(-1)-3|=|-5|=5.
12

Find the vertical asymptote of f(x)=3xx2−4 f(x)=\dfrac{3x}{x^2-4} .

Intermediate
x=2 and x=−2. x=2\text{ and }x=-2.
13

What is the horizontal asymptote of f(x)=3x2x2+1 f(x)=\dfrac{3x^2}{x^2+1} ?

Intermediate

Degrees equal; ratio of leading coefficients.

y=3. y=3.
14

Is f(x)=x4−2x2 f(x)=x^4-2x^2 even, odd, or neither?

Intermediate

f(−x)=x4−2x2=f(x) f(-x)=x^4-2x^2=f(x) .

Even. \text{Even.}
15

Find the inverse of f(x)=2x−1x+3 f(x)=\dfrac{2x-1}{x+3} .

Advanced

Swap x,y x,y and solve: x(y+3)=2y−1⇒y(x−2)=−1−3x x(y+3)=2y-1 \Rightarrow y(x-2)=-1-3x .

f−1(x)=−3x−1x−2. f^{-1}(x)=\dfrac{-3x-1}{x-2}.
16

Find the exact value of sin⁡135∘ \sin 135^\circ .

Intermediate
sin⁡(180∘−45∘)=sin⁡45∘=22. \sin(180^\circ-45^\circ)=\sin45^\circ=\dfrac{\sqrt{2}}{2}.
17

Solve 2sin⁡θ−1=0 2\sin\theta-1=0 for 0∘≤θ<360∘ 0^\circ\le\theta<360^\circ .

Intermediate
sin⁡θ=12⇒θ=30∘ or 150∘. \sin\theta=\tfrac{1}{2} \Rightarrow \theta=30^\circ\text{ or }150^\circ.
18

Find the period of y=3sin⁡(2x) y=3\sin(2x) .

Intermediate
T=2π2=π. T=\dfrac{2\pi}{2}=\pi.
19

Simplify tan⁡θsin⁡θ \dfrac{\tan\theta}{\sin\theta} .

Advanced
sin⁡θ/cos⁡θsin⁡θ=1cos⁡θ=sec⁡θ. \dfrac{\sin\theta/\cos\theta}{\sin\theta}=\dfrac{1}{\cos\theta}=\sec\theta.
20

In triangle ABC ABC , a=8 a=8 , A=30∘ A=30^\circ , B=45∘ B=45^\circ . Find b b .

Advanced
bsin⁡45∘=8sin⁡30∘⇒b=82. \dfrac{b}{\sin45^\circ}=\dfrac{8}{\sin30^\circ} \Rightarrow b=8\sqrt{2}.
21

Find the amplitude and period of y=−4cos⁡ ⁣(πx3) y=-4\cos\!\left(\dfrac{\pi x}{3}\right) .

Intermediate
Amplitude=4;T=2ππ/3=6. \text{Amplitude}=4;\quad T=\dfrac{2\pi}{\pi/3}=6.
22

Convert 210∘ 210^\circ to radians.

Intermediate
210×π180=7π6. 210\times\dfrac{\pi}{180}=\dfrac{7\pi}{6}.
23

Find the distance from (1, −2) (1,\,-2) to (5, 1) (5,\,1) .

Basic
16+9=5. \sqrt{16+9}=5.
24

Find the midpoint of the segment from (−3, 4) (-3,\,4) to (7, −2) (7,\,-2) .

Basic
(−3+72, 4−22)=(2, 1). \left(\dfrac{-3+7}{2},\,\dfrac{4-2}{2}\right)=(2,\,1).
25

Find the equation of the ellipse with semi-axes a=5 a=5 and b=3 b=3 .

Intermediate
x225+y29=1. \dfrac{x^2}{25}+\dfrac{y^2}{9}=1.
26

Find the focus of the parabola y2=12x y^2=12x .

Advanced

4p=12⇒p=3 4p=12 \Rightarrow p=3 .

Focus: (3, 0). \text{Focus: }(3,\,0).
27

Find the asymptotes of x24−y29=1 \dfrac{x^2}{4}-\dfrac{y^2}{9}=1 .

Advanced
y=±32x. y=\pm\dfrac{3}{2}x.
28

A line passes through (2,3) (2,3) and is parallel to 2x−y=5 2x-y=5 . Find its equation.

Intermediate

Slope =2 =2 ; point-slope: y−3=2(x−2) y-3=2(x-2) .

y=2x−1. y=2x-1.
29

Find the area enclosed by y=x2 y=x^2 and y=x+2 y=x+2 . (Use integration concept only.)

Advanced

Intersect at x=−1 x=-1 and x=2 x=2 .

A=∫−12(x+2−x2) dx=[x22+2x−x33]−12=92. A=\int_{-1}^{2}(x+2-x^2)\,dx=\left[\tfrac{x^2}{2}+2x-\tfrac{x^3}{3}\right]_{-1}^{2}=\dfrac{9}{2}.
30

The vertices of a triangle are (0,0) (0,0) , (4,0) (4,0) , (0,3) (0,3) . Find the area.

Basic
A=12×4×3=6. A=\tfrac{1}{2}\times4\times3=6.
31

Find the exterior angle of a regular hexagon.

Intermediate
360∘6=60∘. \dfrac{360^\circ}{6}=60^\circ.
32

Two parallel lines are cut by a transversal. Co-interior angles sum to what?

Basic
180∘. 180^\circ.
33

Find the area of a regular hexagon with side 4.

Advanced
A=332s2=332×16=243. A=\dfrac{3\sqrt{3}}{2}s^2=\dfrac{3\sqrt{3}}{2}\times16=24\sqrt{3}.
34

Two similar triangles have sides in ratio 3:5 3:5 . Find the ratio of their areas.

Intermediate
(35)2=925. \left(\dfrac{3}{5}\right)^2=\dfrac{9}{25}.
35

A tangent from an external point touches the circle at T T . The distance from the external point to the centre is 13 and radius is 5. Find the tangent length.

Intermediate
PT=132−52=144=12. PT=\sqrt{13^2-5^2}=\sqrt{144}=12.
36

Find the volume of a cone with base radius 6 and height 8.

Intermediate
V=13πr2h=13π(36)(8)=96π. V=\tfrac{1}{3}\pi r^2h=\tfrac{1}{3}\pi(36)(8)=96\pi.
37

Find the sum of interior angles of a polygon with 9 sides.

Intermediate
(9−2)×180∘=1260∘. (9-2)\times180^\circ=1260^\circ.
38

The mean of 10 numbers is 15. One number is removed and the new mean is 14. Find the removed number.

Intermediate

Total was 150; new total =9×14=126 =9\times14=126 .

150−126=24. 150-126=24.
39

A data set has standard deviation 3 and mean 20. All values increase by 5. Find the new mean and new standard deviation.

Advanced
New mean=25;Std dev unchanged=3. \text{New mean}=25;\quad\text{Std dev unchanged}=3.
40

A box has 3 red, 4 white, 5 blue cards. Find P(not white) P(\text{not white}) .

Intermediate
P(not white)=812=23. P(\text{not white})=\dfrac{8}{12}=\dfrac{2}{3}.
41

Find lim⁡x→∞3x2+1x2−2 \lim_{x\to\infty}\dfrac{3x^2+1}{x^2-2} .

Advanced
lim⁡x→∞3+1/x21−2/x2=3. \lim_{x\to\infty}\dfrac{3+1/x^2}{1-2/x^2}=3.
42

How many arrangements of the letters CALCULUS exist?

Advanced

8 letters: C×2, A×1, L×3, U×2.

8!2!⋅1!⋅3!⋅2!=1680. \dfrac{8!}{2!\cdot1!\cdot3!\cdot2!}=1680.
43

Find the parametric point on x=2t−1 x=2t-1 , y=t2 y=t^2 at t=3 t=3 .

Intermediate
(2(3)−1,  32)=(5, 9). (2(3)-1,\;3^2)=(5,\,9).
44

Convert the polar point (4, π3) \left(4,\,\dfrac{\pi}{3}\right) to Cartesian coordinates.

Intermediate
x=4cos⁡π3=2;y=4sin⁡π3=23. x=4\cos\dfrac{\pi}{3}=2;\quad y=4\sin\dfrac{\pi}{3}=2\sqrt{3}.
45

Expand (a+b)5 (a+b)^5 and find the coefficient of a2b3 a^2b^3 .

Advanced
(53)=10. \binom{5}{3}=10.
46

A geometric series has a1=5 a_1=5 and r=0.6 r=0.6 . Find S∞ S_\infty .

Intermediate
S∞=51−0.6=12.5. S_\infty=\dfrac{5}{1-0.6}=12.5.
47

Evaluate ∑k=14(2k−1) \sum_{k=1}^{4}(2k-1) .

Intermediate
1+3+5+7=16. 1+3+5+7=16.
48

A box has 5 red and 3 blue balls. Find the probability that 3 drawn (without replacement) are all red.

Advanced
58×47×36=60336=528. \dfrac{5}{8}\times\dfrac{4}{7}\times\dfrac{3}{6}=\dfrac{60}{336}=\dfrac{5}{28}.
49

If P(A)=0.6 P(A)=0.6 and P(B∣A)=0.4 P(B|A)=0.4 , find P(A∩B) P(A\cap B) .

Advanced
P(A∩B)=P(B∣A)⋅P(A)=0.4×0.6=0.24. P(A\cap B)=P(B|A)\cdot P(A)=0.4\times0.6=0.24.
50

Using Bayes' theorem: P(A)=0.3 P(A)=0.3 , P(B∣A)=0.8 P(B|A)=0.8 , P(B∣A‾)=0.2 P(B|\overline{A})=0.2 . Find P(A∣B) P(A|B) .

Advanced

P(B)=0.3×0.8+0.7×0.2=0.38 P(B)=0.3\times0.8+0.7\times0.2=0.38 .

P(A∣B)=0.3×0.80.38=0.240.38≈0.632. P(A|B)=\dfrac{0.3\times0.8}{0.38}=\dfrac{0.24}{0.38}\approx0.632.
✎

Test generator

Build a randomised ACT 2 Math Level 1 mini-test from the question bank, or generate a complete 50-question full-length paper structured like the ACT International Subject Test — Mathematics 1: 60 minutes, calculator permitted.

Full official exam paper

Generates a complete 50-question ACT International Subject Test — Mathematics 1 paper: one section, 60 minutes, calculator permitted, about half Algebra II and half precalculus.

↓

Downloads

Take the ACT 2 Math Level 1 material offline. The PDF prints from your browser; the Word packet contains editable OMML equations for classroom customisation.

PDF · ready now

ACT 2 Math Level 1 — notes & practice

All eight advanced chapters plus every worked solution — algebra, functions, trig, pre-calc, and statistics.

DOCX · on request

Native Word packet

Editable .docx with real Word equations (OMML) — all ACT 2 Math Level 1 topics ready for classroom printing.

Official · Past Papers

Past Papers & Official Tests

Officially released exams and mark schemes from the examining body.

Worksheet Library

8 original ClipSAT worksheets with full answer keys, organized by unit — free to download and print.

Loading worksheet library…

Mock Exam

--:--