Level 3 Differentiation Walkthrough

2019 NCEA Level 3 Differentiation Question 3(c)

2019 Paper

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Walkthrough overview

What this question practises

This 2019 walkthrough is part of AS91578 — Apply differentiation methods in solving problems.

Method: Maximising a rectangle area under \(y=4-\sqrt{x}\).

This is Question 3(c) from the 2019 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 maximising a rectangle area under \(y=4-\sqrt{x}\). Use the hints to plan the method, then repeat the question without hints and check each step.

Common mistake to avoid

Finding a stationary value is only part of an optimisation argument; justify that it is the required maximum and respect the domain.

Continue practising

← Question 3(b) Question 3(d) →