Question

I am trying to figure this question: 1 + tan^2A = Sec^2A

Answer 1

Answer:

see explanation

Step-by-step explanation:

Using the Pythagorean identity

cos²A + sin²A = 1 ( divide terms by cos²A )

$\frac{cos^2A}{cos^2A}$ + $\frac{sin^2A}{cos^2A}$ = $\frac{1}{cos^2A}$ , that is

1 + tan²A = sec²A ← as required