Question Detail

MTH 102 MTH 102 Past Questions Objective Question

Question

Simplify the integral ∫ 3x2ex3 dx.
Options
A e<sup>x<sup>2</sup></sup> + C
B e<sup>x<sup>3</sup></sup> + C
Correct Answer
C e<sup>x<sup>4</sup></sup> + C
D e<sup>x<sup>5</sup></sup> + C
Correct Answer

Option B is the correct answer.

Detailed Explanation

This integral can be solved using u-substitution.Let u = x3.Then, find the derivative of u with respect to x: du/dx = 3x2.So, du = 3x2 dx.Substitute u and du into the integral: ∫ eu du.The integral of eu with respect to u is eu + C.Substitute x3 back for u: ex3 + C.This matches option B.

Hint

Identify a part of the integrand whose derivative is also present in the integrand (up to a constant factor).

Question Info