Prove the identity\(\frac{1-{tan}^{2}x}{cos2x}\equiv{sec}^{2}xx\neq\frac{2k+1}{4} \pi\)

Prove the identity\(\frac{1-{tan}^{2}x}{cos2x}\equiv{sec}^{2}xx\neq\frac{2k+1}{4} \pi\) - চর্চা