The derivative of \(f(x) = \sin(x^{3} + 6)\) with respect to x is
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → \(3x^{2}\cos(x^{3} + 6)\)
Let \(u = x^{3} + 6\), so \(f = \sin u\). By the chain rule, the derivative of the outer function is multiplied by the derivative of the inner one:
\( \displaystyle f'(x) = \cos u \cdot \frac{du}{dx} \)
\( = \cos(x^{3} + 6) \cdot 3x^{2} \)
\( = 3x^{2}\cos(x^{3} + 6) \)