Topic module

Exponentials and Logarithms

Interpret exponential graphs, apply logarithm laws and solve equations reducible to exponential form.

Long-form learning
Concept to Risk to Memory to Check-up

How to prepare for the current TMUA

Secure the shared mathematical specification, practise application in unfamiliar settings, then make every Paper 2 implication and proof step explicit.

Core concepts

Concept 1

Connect an exponential statement with its inverse logarithmic statement.

Exam cue: Check the base and positivity conditions.

Concept 2

Combine and expand logarithms using product, quotient and power laws.

Exam cue: Look for a repeated expression such as aˣ.

Concept 3

Reduce compound exponential equations through factorisation or substitution.

Exam cue: Verify candidate solutions in the original equation.

Risk pitfalls and guardrails

Splitting the logarithm of a sum.

Guardrail: Do not treat examples as proof, reverse an implication, cancel a possible zero or rely on calculator-only intuition.

Allowing a non-positive logarithm argument.

Guardrail: Do not treat examples as proof, reverse an implication, cancel a possible zero or rely on calculator-only intuition.

Using the excluded change-of-base formula as assumed knowledge.

Guardrail: Do not treat examples as proof, reverse an implication, cancel a possible zero or rely on calculator-only intuition.

Memory anchors

Inverse pair

aˣ = b exactly when x = logₐb.

Product law

logₐx + logₐy = logₐ(xy).

Quotient law

logₐx − logₐy = logₐ(x/y).

Power law

k logₐx = logₐ(xᵏ).

Log domain

Every real logarithm argument must be positive.

Repeated power

Substitute u = aˣ when an exponential equation is quadratic in aˣ.

Checkpoint rule

Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.

Knowledge Check (after reading)

Short check-up to confirm understanding of this module.

Check-up Questions

1-2 question checkpoint

If 2^(x+1)=32, what is x²−1?

The equation 9^x=27^(x−1) has solution x. What is 6x?

Answer all questions to submit.

Next step personalized recommendations

Continue learning

Move forward only after this module is stable.

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