## LaddiusMaximus 5 years ago (1-sin^2x)/cos^2x How does that equal one? Im doing trigonometric identities and im stuck.

1. anonymous

Assuming you mean,$\frac{1-\sin^2x}{\cos^2x}$you have recall the fact$\cos^2x+\sin^2x=1$so that$1-\sin^2x=\cos^2x$hence$\frac{1-\sin^2x}{\cos^2x}=\frac{\cos^2x}{\cos^2x}=1$

2. anonymous

Consider the fact, that's not solvable, if $x=(n+0.5)\cdot\pi$ with $n \in \mathbb{Z}$