Level 3 Differentiation Walkthrough

2025 NCEA Level 3 Differentiation Question 2(b)

2025 Paper

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Walkthrough overview

What this question practises

This 2025 walkthrough is part of AS91578 — Apply differentiation methods in solving problems.

Method: Product rule and deciding whether a model is increasing or decreasing.

This is Question 2(b) from the 2025 NCEA Level 3 Differentiation paper for AS91578 — Apply differentiation methods in solving problems. Use the guided hints to practise the method before revealing the full working.

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Learning summary

Review the method, not only the answer

This walkthrough helps you practise product rule and deciding whether a model is increasing or decreasing. Use the hints to plan the method, then repeat the question without hints and check each step.

Common mistake to avoid

Differentiate both factors in turn and keep both product-rule terms.

Continue practising

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