Evaluate ∫ cot 2x dx. A. 1⁄2 Ln csc 2x + C B. 1⁄2 Ln cos 2x + C C. 1⁄2 Ln sin 2x + C D. 1⁄2 Ln sec 2x + C

Cot (2x) dx = [cos (2x) / sin (2x) ] dx, and note that the derivative of sin (2x) = 2cos (2x) dx, which is double of the numerator.

Therefore, this can be integrated using an ln function of sin. This results in:

(1/2) ln (sin2x) + C

This is choice C.