Question Detail

MTH 102 MTH 102 Past Questions Objective Question

Question

Obtain the integral ∫log x dx
Options
A x(log x+1)
B x(log x-1)
Correct Answer
C -x(log x+1)
D x(1-log x)
Correct Answer

Option B is the correct answer.

Detailed Explanation

To integrate ∫log x dx (assuming natural logarithm, ln x), we use integration by parts, ∫u dv = uv - ∫v du.Let u = ln x and dv = dx.Then du = (1/x) dx and v = x.∫ln x dx = x ln x - ∫x (1/x) dx= x ln x - ∫1 dx= x ln x - x + C= x(ln x - 1) + CThis matches option B.

Hint

Use integration by parts, setting u = ln x and dv = dx.

Question Info