What functions are examined in VCE Math Methods Units 3 and 4?

Five families. Polynomial functions up to quartic (with focus on cubics and quartics), power functions including rational powers like square root and cube root, exponential functions (most often base e), logarithmic functions (most often natural log), and circular (trig) functions including sin, cos and tan with their unit-circle exact values. Each family has its standard graph, its transformations, and its standard exam patterns.

What is the standard form of a transformation in VCE Math Methods?

The convention is $y = a \cdot f(b(x - h)) + k$. Here $a$ is a vertical dilation (and reflection if negative), $b$ is the reciprocal of a horizontal dilation (so $b = 2$ horizontally compresses by a factor of 2), $h$ is a horizontal translation right, and $k$ is a vertical translation up. The order of operations matters when describing transformations in words. VCAA marking guides usually accept either order if the algebra is consistent.

What is an inverse function and when does it exist?

The inverse of $f$ is the function $f^{-1}$ that undoes $f$, so $f^{-1}(f(x)) = x$ for all $x$ in the domain. An inverse exists only when $f$ is one-to-one (each y-value corresponds to exactly one x-value). For functions that are not one-to-one (e.g. $f(x) = x^2$ on all of $\mathbb{R}$), restrict the domain to make it one-to-one before taking the inverse. The graph of $f^{-1}$ is the reflection of $f$ in the line $y = x$.

How do composite functions work and where are they examined?

A composite function $f \circ g$ is defined by $(f \circ g)(x) = f(g(x))$. For the composite to exist, the range of $g$ must be a subset of the domain of $f$. VCAA examines composite functions in three patterns. (1) Compute $f(g(2))$ directly. (2) Determine the rule and domain of $f \circ g$ for a given $f$ and $g$. (3) Determine for which values of a parameter the composite is defined.

What are the unit circle exact values I need for Paper 1?

At minimum, the exact sin, cos and tan values at $0$, $\pi/6$, $\pi/4$, $\pi/3$, $\pi/2$ and their multiples up to $2\pi$. Memorise the pattern $\sin(\pi/6) = 1/2$, $\sin(\pi/4) = \sqrt{2}/2$, $\sin(\pi/3) = \sqrt{3}/2$. Then use the quadrant signs (ASTC, all-students-take-calculus, in quadrants 1-2-3-4) to extend across the full circle. Paper 1 will have at least one question requiring these without a calculator.

What is the factor theorem and how is it used?

The factor theorem says that if $f(a) = 0$, then $(x - a)$ is a factor of the polynomial $f(x)$. The most common Paper 1 application is to factorise a cubic. Step 1, find one root by trial (often $\pm 1$, $\pm 2$, or a simple fraction). Step 2, use polynomial long division or synthetic division to divide out that factor. Step 3, factorise the resulting quadratic. This is standard Paper 1 technique that you should be able to do in under 4 minutes.

VICMath Methods

VCE Math Methods functions, graphs and transformations: the 2026 guide

A complete guide to VCE Math Methods Areas of Study 1 and 2 for Units 3 and 4. Polynomial, exponential, logarithmic and circular functions, transformations (dilation, reflection, translation), composite and inverse functions, plus the algebra you need without CAS in Paper 1.

Generated by Claude Opus 4.820 min readVCAA-MM-AOS-1-2Updated 2026-06-21

Reviewed by: AI editorial process; not yet individually human-reviewed

Jump to a section

What functions and transformations are really asking
Polynomial functions
Exponential and logarithmic functions
Circular (trig) functions
Transformations
Composite and inverse functions
How functions and transformations are examined
Practice strategy
Check your knowledge

What functions and transformations are really asking

VCE Math Methods Areas of Study 1 and 2 cover the function families and the algebra you need to manipulate them. Together they account for roughly 40 percent of the course content and a similar share of exam marks.

These areas are where Paper 1 (Tech-Free) lives most heavily. CAS calculators trivialise much of the calculus and statistics work, but Paper 1 forces students to do polynomial division, exact-value trig, log laws, and transformation algebra by hand. Students who skip this fluency rely on Paper 2 (Tech-Active) marks and cap their study scores in the high 30s.

Polynomial functions

The standard polynomial families examined are quadratic ( $f(x) = ax^2 + bx + c$ ), cubic ( $f(x) = ax^3 + bx^2 + cx + d$ ), and quartic. Their key features:

Quadratic. One turning point. Discriminant $\Delta = b^2 - 4ac$ tells you the number of real roots. The vertex is at $x = -b/(2a)$ .
Cubic. Up to two turning points. Always has at least one real root. Standard factored forms include $f(x) = a(x - p)(x - q)(x - r)$ for three distinct roots and $f(x) = a(x - p)^2(x - q)$ for a repeated root at $x = p$ .
Quartic. Up to three turning points. May have 0, 2 or 4 real roots. The most common quartic examined has two repeated roots, $f(x) = a(x - p)^2(x - q)^2$ .

The factor and remainder theorems

Remainder theorem. When polynomial $f(x)$ is divided by $(x - a)$ , the remainder is $f(a)$ .

Factor theorem. $(x - a)$ is a factor of $f(x)$ if and only if $f(a) = 0$ .

Factorise

f(x) = x^3 - 4x^2 + x + 6

over the rationals (Tech-Free)

Step 1. Trial small integer roots to find one factor. The factor theorem says $f(a) = 0$ implies $(x - a)$ is a factor.

$f(-1) = -1 - 4 - 1 + 6 = 0$ , so $(x + 1)$ is a factor.

Step 2. Divide $f(x)$ by $(x + 1)$ . Use polynomial long division (or synthetic division) to peel off the known linear factor.

x^3 - 4x^2 + x + 6 = (x + 1)(x^2 - 5x + 6)

Step 3. Factorise the resulting quadratic. Find two numbers that multiply to $6$ and sum to $-5$ .

x^2 - 5x + 6 = (x - 2)(x - 3)

Step 4. Combine. Write the fully factored cubic.

f(x) = (x + 1)(x - 2)(x - 3)

Answer. $f(x) = (x + 1)(x - 2)(x - 3)$ . The roots are $x = -1, 2, 3$ .

Exponential and logarithmic functions

The default exponential and log in VCE Math Methods are base $e$ (the natural exponential and natural log, $\ln$ ).

Exponential. $f(x) = e^x$ has domain $\mathbb{R}$ , range $(0, \infty)$ , horizontal asymptote $y = 0$ . Always positive. Increasing for $x \in \mathbb{R}$ .

Logarithm. $f(x) = \ln(x)$ has domain $(0, \infty)$ , range $\mathbb{R}$ , vertical asymptote $x = 0$ . The inverse of $e^x$ . The graphs reflect across $y = x$ .

Log laws (these are Paper 1 staples):

$\ln(ab) = \ln(a) + \ln(b)$
$\ln(a/b) = \ln(a) - \ln(b)$
$\ln(a^n) = n \ln(a)$
Change of base: $\log_b(a) = \ln(a) / \ln(b)$

Solve

e^{2x} - 5e^x + 6 = 0

exactly (Tech-Free)

Step 1. Make the hidden quadratic visible with a substitution. Setting $u = e^x$ converts the equation into a standard quadratic in $u$ .

Let $u = e^x$ , so $u^2 = e^{2x}$ .

Step 2. Rewrite in $u$ . Substitute into the original equation.

u^2 - 5u + 6 = 0

Step 3. Factorise and solve for $u$ . Two numbers multiplying to $6$ and summing to $-5$ .

(u - 2)(u - 3) = 0 \implies u = 2 \text{ or } u = 3

Step 4. Reverse the substitution. Solve $e^x = u$ by taking $\ln$ of both sides.

$e^x = 2$ gives $x = \ln 2$ . $e^x = 3$ gives $x = \ln 3$ .

Step 5. Verify both values are valid. Both $\ln 2$ and $\ln 3$ are real, and there is no domain restriction on $e^x$ , so both are accepted.

Answer. $x = \ln 2$ or $x = \ln 3$ .

Circular (trig) functions

The three primary trig functions in VCE Math Methods are sin, cos and tan, all in radians.

Standard exact values (Paper 1 essential).

angle	sin	cos	tan
$0$	$0$	$1$	$0$
$\pi/6$	$1/2$	$\sqrt{3}/2$	$1/\sqrt{3}$
$\pi/4$	$\sqrt{2}/2$	$\sqrt{2}/2$	$1$
$\pi/3$	$\sqrt{3}/2$	$1/2$	$\sqrt{3}$
$\pi/2$	$1$	$0$	undefined

The unit-circle signs (ASTC): in quadrant 1, all positive. Quadrant 2, sin positive only. Quadrant 3, tan positive only. Quadrant 4, cos positive only.

Standard transformation form. $y = a \sin(b(x - h)) + k$ has amplitude $|a|$ , period $2\pi/b$ , horizontal shift $h$ , and midline $y = k$ .

Solve

2\sin(2x) = \sqrt{3}

for

x \in [0, 2\pi]

(Tech-Free)

Step 1. Isolate the trig term. Divide both sides by 2 so the equation matches the unit-circle table.

\sin(2x) = \frac{\sqrt{3}}{2}

Step 2. Expand the search interval for the argument $2x$ . Because the argument is $2x$ , while $x \in [0, 2\pi]$ we need $2x \in [0, 4\pi]$ .

Step 3. List all solutions of $\sin(\theta) = \sqrt{3}/2$ in $[0, 4\pi]$ . From the table, $\sin(\pi/3) = \sqrt{3}/2$ . Sine is positive in quadrants 1 and 2, so within one period the solutions are $\pi/3$ and $\pi - \pi/3 = 2\pi/3$ . Add $2\pi$ to each to fill $[0, 4\pi]$ .

2x \in \left\{\frac{\pi}{3}, \frac{2\pi}{3}, \frac{7\pi}{3}, \frac{8\pi}{3}\right\}

Step 4. Solve for $x$ . Divide each by 2.

x \in \left\{\frac{\pi}{6}, \frac{\pi}{3}, \frac{7\pi}{6}, \frac{4\pi}{3}\right\}

Answer. Four solutions, $x = \frac{\pi}{6}, \frac{\pi}{3}, \frac{7\pi}{6}, \frac{4\pi}{3}$ .

Transformations

The standard transformation form in VCE Math Methods is $y = a \cdot f(b(x - h)) + k$ . The four components.

$a$ (vertical dilation by factor $|a|$ , reflection in the x-axis if $a < 0$ ). Multiplies y-values.
$b$ (horizontal dilation by factor $1/|b|$ , reflection in the y-axis if $b < 0$ ). Compresses or stretches x-values. Note the reciprocal: $b = 2$ compresses horizontally by factor 2.
$h$ (horizontal translation right by $h$ ). Negative $h$ means translation left.
$k$ (vertical translation up by $k$ ). Negative $k$ means translation down.

Order of operations. When describing transformations in words, the conventional order is dilation, reflection, then translation. So $y = 2\sin(3(x - \pi/4)) + 1$ is "dilation by factor 2 from the x-axis, dilation by factor 1/3 from the y-axis, translation $\pi/4$ to the right, translation 1 up."

Describe and sketch

g(x) = \begin{cases} -(x+2)^2 + 4 & \text{if } x \leq 0 \\ \sqrt{x} & \text{if } x > 0 \end{cases}

as a piecewise transformation (Tech-Free)

Step 1. Identify each piece as a transformation of a parent function. Match each branch against a base shape.

The first branch is a transformed parabola. The base is $y = x^2$ , then horizontal translation 2 left, reflection in the x-axis, and vertical translation 4 up. The second branch is the base square-root function $y = \sqrt{x}$ with no transformation.

Step 2. Sketch the parabola branch on $x \leq 0$: Vertex at $(-2, 4)$ , opens downward (because of the negative coefficient). It passes through $x$ -intercepts where $-(x+2)^2 + 4 = 0$ , i.e. $(x + 2)^2 = 4$ , so $x = 0$ or $x = -4$ . Restrict to $x \leq 0$ , so the relevant intercepts are $(-4, 0)$ and $(0, 0)$ .
Step 3. Sketch the square-root branch on $x > 0$: Starts at the open point near $(0, 0)$ , climbs slowly. At $x = 1$ , $y = 1$ . At $x = 4$ , $y = 2$ .
Step 4. Check continuity at the join $x = 0$: Left limit: $-(0+2)^2 + 4 = 0$ . Right limit: $\lim_{x \to 0^+}\sqrt{x} = 0$ . They match, so $g$ is continuous at $x = 0$ .
Step 5. State the range: The parabola branch on $x \leq 0$ ranges over $[0, 4]$ . The square-root branch on $x > 0$ ranges over $(0, \infty)$ . Their union is $[0, \infty)$ .
Answer: Continuous piecewise function, parabola on $x \leq 0$ with vertex $(-2, 4)$ , square-root on $x > 0$ , domain $\mathbb{R}$ , range $[0, \infty)$ .

Composite and inverse functions

Composite functions

$(f \circ g)(x) = f(g(x))$ .

Existence condition. The range of $g$ must be a subset of the domain of $f$ . If not, $f \circ g$ is not defined.

Determine whether

f \circ g

exists for

f(x) = \ln(x)

and

g(x) = x^2 - 4

, and find the maximal restriction (Tech-Free, composite existence)

Step 1. List the domain and range of each function. Existence depends on the range of $g$ fitting inside the domain of $f$ .

$f$ has domain $(0, \infty)$ and range $\mathbb{R}$ . $g$ has domain $\mathbb{R}$ and range $[-4, \infty)$ .

Step 2. Check the existence condition. Is the range of $g$ a subset of the domain of $f$ ?

No. The range of $g$ includes $0$ and negative numbers (e.g. $g(0) = -4$ ), which are not in the domain of $f$ . So $f \circ g$ is not defined on all of $\mathbb{R}$ .

Step 3. Restrict the domain of $g$ to where $g(x) > 0$ . Solve $x^2 - 4 > 0$ .

$x^2 > 4 \implies |x| > 2 \implies x \in (-\infty, -2) \cup (2, \infty)$ .

Step 4. State the rule and domain of the composite. Combine the restriction with the composition.

$(f \circ g)(x) = \ln(x^2 - 4)$ , with domain $(-\infty, -2) \cup (2, \infty)$ .

Answer. The unrestricted composite is undefined; the maximal restriction has domain $(-\infty, -2) \cup (2, \infty)$ and rule $\ln(x^2 - 4)$ .

Inverse functions

For $f^{-1}$ to exist, $f$ must be one-to-one.

Finding the inverse. Swap $x$ and $y$ , then solve for $y$ .

Graphical property. The graph of $f^{-1}$ is the reflection of $f$ in the line $y = x$ .

Domain of $f^{-1}$ : equals the range of $f$ . Range of $f^{-1}$ : equals the domain of $f$ . Pay attention to domain restrictions; they often appear in Paper 2 multi-part questions.

Decide whether

f(x) = x^2 - 6x + 5

has an inverse on

\mathbb{R}

, and find the inverse of the restriction

f: [3, \infty) \to \mathbb{R}

(Tech-Free, inverse existence)

Step 1. Check whether $f$ is one-to-one on $\mathbb{R}$ . A quadratic on $\mathbb{R}$ is never one-to-one because of its axis of symmetry.

Complete the square: $f(x) = (x - 3)^2 - 4$ . The axis of symmetry is $x = 3$ , so $f(0) = 5 = f(6)$ . Not one-to-one, so no inverse exists on $\mathbb{R}$ .

Step 2. Identify the range of the restriction. On $[3, \infty)$ , $f$ is increasing (the right branch of the parabola).

The minimum is at $x = 3$ with $f(3) = -4$ . So the range of $f$ on $[3, \infty)$ is $[-4, \infty)$ .

Step 3. Swap $x$ and $y$ and solve for $y$ . Use the completed-square form.

Start: $y = (x - 3)^2 - 4$ . Swap: $x = (y - 3)^2 - 4$ , so $(y - 3)^2 = x + 4$ .

Step 4. Take the appropriate square root. Because the restricted domain is $[3, \infty)$ , we need $y \geq 3$ , so take the positive root.

y - 3 = \sqrt{x + 4} \implies y = 3 + \sqrt{x + 4}

Step 5. State the inverse with its domain and range. The domain of $f^{-1}$ equals the range of $f$ , and the range of $f^{-1}$ equals the domain of $f$ .

$f^{-1}: [-4, \infty) \to [3, \infty)$ , $f^{-1}(x) = 3 + \sqrt{x + 4}$ .

Answer. No inverse on $\mathbb{R}$ . The restriction to $[3, \infty)$ has inverse $f^{-1}(x) = 3 + \sqrt{x + 4}$ with domain $[-4, \infty)$ and range $[3, \infty)$ .

Solve the system

y = x^2 - 2x

and

y = 2x - 4

simultaneously (Tech-Free, simultaneous solutions)

Step 1. Equate the right-hand sides. Both equations are solved for $y$ , so set them equal to eliminate $y$ .

x^2 - 2x = 2x - 4

Step 2. Rearrange to a standard quadratic. Move all terms to one side.

x^2 - 4x + 4 = 0

Step 3. Factorise. Recognise the perfect square.

(x - 2)^2 = 0 \implies x = 2 \text{ (double root)}

Step 4. Find the corresponding $y$ . Substitute $x = 2$ into either equation; the line is faster.

$y = 2(2) - 4 = 0$ .

Step 5. Interpret the double root. Since the quadratic has a repeated root, the line is tangent to the parabola at the single intersection.

Answer. One intersection point at $(2, 0)$ ; the line $y = 2x - 4$ is tangent to the parabola at this point.

Common Paper 1 traps

Skipping the by-hand algebra: Paper 1 has no CAS. If you cannot do polynomial division, exact-value trig, or log manipulation cleanly without a calculator, you will lose marks at speed.
Forgetting domain restrictions on inverses: When you restrict the domain of $f$ to make it one-to-one, the resulting $f^{-1}$ has a corresponding restricted range. Markers reward stating the domain and range explicitly.
Transformation order confusion: When described in words, "translate then dilate" produces a different graph than "dilate then translate." Use the standard form $y = a f(b(x - h)) + k$ and identify the four parameters; this avoids the trap.
Trig domain errors: When solving $\sin(2x) = 1/2$ for $x \in [0, 2\pi]$ , the doubling of $x$ doubles the number of solutions. Find all solutions in the wider interval $[0, 4\pi]$ for $2x$ , then divide by 2.
Missing the negative root: $\sqrt{x^2} = |x|$ , not $x$ . When you take square roots in equation-solving, write $\pm$ unless the context tells you which sign to keep.

How functions and transformations are examined

In the VCE Math Methods exams:

Paper 1 (Tech-Free). Roughly 12-15 marks across the two areas. Standard patterns include factorise this cubic, solve this exponential equation exactly, sketch this transformed function with key features, find the rule of this transformed function from a graph.
Paper 2 Section A (Tech-Active, multiple choice). 6-8 multiple-choice questions across the two areas. Standard patterns include identify the transformation, find the inverse, determine the domain of a composite.
Paper 2 Section B (Tech-Active, extended response). Often a long modelling question that uses a function from one of the families (a logistic-like rational function for population growth, a sinusoidal model for tides). These integrate calculus too.

Practice strategy

For VCE Math Methods functions and transformations:

Terms 1 and 2 of Year 12. Master the factor theorem, log laws, exact-value trig. These are SAC content too.
Term 3. Drill Paper 1 algebra weekly. Aim for 30-40 short questions per week from past VCAA papers (2023 onwards under the current study design).
Term 4. Full timed Paper 1 papers. Score Paper 1 separately to identify weak areas before the final week.

See our VCE Math Methods practice questions for prompts modelled on VCAA past papers.

Check your knowledge

Eight questions, increasing in difficulty. Attempt the Tech-Free set without a calculator; Tech-Active questions may use CAS.

Tech-Free (Paper 1 style)

Factorise $f(x) = 2x^3 + x^2 - 7x - 6$ over the rationals.
Solve $\log_2(x) + \log_2(x - 3) = 2$ for $x$ .
Solve $\cos(x) = -\frac{1}{2}$ for $x \in [0, 2\pi]$ .
The function $f(x) = 3(x - 1)^2 + 2$ is given. State the transformations applied to $y = x^2$ to produce $f$ , and state the range.
Find the inverse of $f(x) = \frac{2x + 1}{x - 3}$ , $x \neq 3$ .

Tech-Active (Paper 2 style)

Let $f(x) = \ln(x - 2)$ and $g(x) = e^{2x} + 2$ . State the range of $g$ and explain why $f \circ g$ exists for all $x \in \mathbb{R}$ .
The function $h(x) = a\sin(b x) + c$ has amplitude 3, period $\pi$ , and midline $y = -1$ , with $a > 0$ and $b > 0$ . State the values of $a$ , $b$ and $c$ .
Find the values of $k$ for which the system $y = x^2 + 1$ and $y = kx$ has exactly two solutions.

Solutions

Q1: Trial $x = -1$ : $f(-1) = -2 + 1 + 7 - 6 = 0$ , so $(x + 1)$ is a factor. Divide: $2x^3 + x^2 - 7x - 6 = (x + 1)(2x^2 - x - 6)$ . Factorise the quadratic: $2x^2 - x - 6 = (2x + 3)(x - 2)$ . Final: $f(x) = (x + 1)(2x + 3)(x - 2)$ .
Q2: Combine using the log product law: $\log_2(x(x - 3)) = 2$ , so $x(x - 3) = 4$ , giving $x^2 - 3x - 4 = 0$ and $(x - 4)(x + 1) = 0$ . So $x = 4$ or $x = -1$ . The original $\log_2(x)$ requires $x > 0$ and $\log_2(x - 3)$ requires $x > 3$ . Only $x = 4$ satisfies both.
Q3: $\cos$ is negative in quadrants 2 and 3. The reference angle for $\cos = 1/2$ is $\pi/3$ . So $x = \pi - \pi/3 = 2\pi/3$ or $x = \pi + \pi/3 = 4\pi/3$ .
Q4: Compared to $y = x^2$ : dilation by factor 3 from the x-axis, translation 1 to the right, translation 2 up. The vertex is at $(1, 2)$ and the parabola opens upward, so the range is $[2, \infty)$ .
Q5: Swap $x$ and $y$ : $x = \frac{2y + 1}{y - 3}$ . Multiply through: $x(y - 3) = 2y + 1$ , so $xy - 3x = 2y + 1$ and $y(x - 2) = 3x + 1$ . Solve: $y = \frac{3x + 1}{x - 2}$ . So $f^{-1}(x) = \frac{3x + 1}{x - 2}$ , $x \neq 2$ .
Q6: The range of $g(x) = e^{2x} + 2$ is $(2, \infty)$ because $e^{2x} > 0$ for all $x$ . The domain of $f(x) = \ln(x - 2)$ is $(2, \infty)$ . Since the range of $g$ is a subset of the domain of $f$ (in fact they are equal as open intervals), $f \circ g$ exists for all $x \in \mathbb{R}$ . The rule is $(f \circ g)(x) = \ln(e^{2x} + 2 - 2) = \ln(e^{2x}) = 2x$ .
Q7: Amplitude $3$ gives $a = 3$ . Period $\pi$ gives $b = 2\pi / \pi = 2$ . Midline $y = -1$ gives $c = -1$ . So $h(x) = 3\sin(2x) - 1$ .
Q8: Equate: $x^2 + 1 = kx$ , so $x^2 - kx + 1 = 0$ . For exactly two solutions the discriminant must be strictly positive: $k^2 - 4 > 0$ , so $k^2 > 4$ , giving $k < -2$ or $k > 2$ .