If , then is equal to:

Answer and explanation

Correct answer: A.

  1. Step 1: Use the product rule with , .
  2. Step 2: and .
  3. Step 3: .
Answer
.
Why not the others: Swapping the 2 and 3, or pairing the multipliers with the wrong trig function, breaks the chain rule; a minus sign belongs to the derivative of cosine, not sine.

Practise more Calculus: Differentiation and Optimization.

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

If y = e 2x sin (3x), then dy/dx is equal to: | Victorian VCE