Question Detail

MTH 102 MTH 102 Past Questions Objective Question

Question

Evaluate ∫ Cos(ln x)/x dx
Options
A sec(lnx) + C
B tan(lnx) + C
C cot(lnx) + C
D sin(lnx) + C
Correct Answer
Correct Answer

Option D is the correct answer.

Detailed Explanation

To evaluate the integral ∫ Cos(ln x)/x dx, we use a substitution. Let u = ln x. Then, the differential du = (1/x) dx. Substituting these into the integral, we get ∫ Cos(u) du. The integral of Cos(u) with respect to u is sin(u) + C. Finally, substitute back u = ln x to get the result: sin(lnx) + C.

Hint

Consider a substitution for the argument of the cosine function.

Question Info