Question

Show that
$cos^{4} \alpha + 2cos^{2} (1 - \frac{1}{sec ^{2} \alpha } ) = 1 - sin ^{4} \alpha$
​

Answer 1

Step-by-step explanation:

mark me as brainiest. thanks

Answer 2

Answer:

$\frac{1}{sec {}^{2} \alpha } = cos {}^{2} \alpha$

$cos^{4} \alpha + 2cos^{2} (1 - \cos {}^{2} \alpha )$