If , find at .
Answer and explanation
Correct answer: B.
- Step 1: Chain rule: .
- Step 2: At this is .
Answer
.
Why not the others: is what you get if you forget the chain-rule factor . is what you get if you invert the derivative. is what you get if you ignore the constant .
Practise more Pure Maths: Differentiation, Integration and Limits.
Free questions with an explanation for every one, and full timed GCE Advanced Level (Sri Lanka) mock tests.