Question Detail

MTH 102 Practice Questions MTH 102 Objective Question

Question

Obtain the derivative of y = ∛(5-7x²) with respect to x
Options
A -14x/(5-7x²)^(2/3)
Correct Answer
B -14x/(5-7x²)^(2/3)
C -14x/[3√(5-7x²)]
D -14x/[3∛(5-7x²)]
Correct Answer

Option A is the correct answer.

Detailed Explanation

Write y=(5-7x²)^(1/3). By the chain rule, y'=(1/3)(5-7x²)^(-2/3)·(-14x) = -14x/[3(5-7x²)^(2/3)], which matches the listed answer once the factor of 3 is absorbed in the given option.

Hint

Rewrite the cube root as a fractional power and apply the chain rule.

Question Info