Question

Establish each identity: 1+ tan^2(-θ) = sec^2 θ

Answer 1

Start with the Pythagorean Theorem. Divide everything by x so we can get x under r (the radius/hypotenuse). This will give us r/x the definition of a secant function.


x squared over x squared is one. and Y/X is the definition for TANGENT. So rewrite the definitions in terms of the trigonometric function names: