Question

Solve: ${\sin }^2\theta >{\cos }^2\theta$

Answer 1

Given, ${\sin }^2\theta >{\cos }^2\theta$

$\frac{{\sin }^2\theta }{{\cos }^2\theta }>1$

$\Rightarrow {\tan }^2\theta >1$ ............ $[\frac{\sin \theta }{\cos \theta }=\tan \theta ]$

$\Rightarrow {\tan }^2\theta >{\left(1\right)}^2$

$\Rightarrow \theta >n\pi \pm \frac{\pi }{4}$