Question Detail
Question
Evaluate the integral ∫ (e2x + e-2x) / (e2x - e-2x) dx.
Correct Answer
Option C is the correct answer.
Detailed Explanation
This integral can be solved using substitution.Let u = e2x - e-2x.Then, calculate du/dx:du/dx = d/dx(e2x) - d/dx(e-2x) = 2e2x - (-2e-2x) = 2e2x + 2e-2x = 2(e2x + e-2x).So, du = 2(e2x + e-2x) dx, which means (e2x + e-2x) dx = (1/2) du.Substitute u and du into the integral:∫ (1/u) * (1/2) du = (1/2) ∫ (1/u) du = (1/2)ln|u| + C.Substitute u back: (1/2)ln|e2x - e-2x| + C.This matches option C.
Hint
Look for a substitution where the numerator is proportional to the derivative of the denominator.