Answer and explanation

Correct answer: A.

  1. Step 1: Write and use the product rule: .
  2. Step 2: Factor: .
Answer
.
Why not the others: The derivative of is ; drops the second term; drops the first term.

Practise more Calculus: Differentiation and Optimization.

Free questions with an explanation for every one, and full timed Victorian VCE mock tests.