Question

Check all that apply. Which of the following equation is answer for the equation: sec 2x=. ______. A. 1/cos^2x - sin^2x. B. 1/sin^2x - cos^2x. C. 1/2sin^2x - 1. D. 1/1-2sin^2x

Answer 1

Sec x = 1/cos x
cos 2x = cos^2 x - sin^2 x
sec 2x = 1/(cos^2 x - sin^2 x)

Option A is the correct answer.