Trigonometry Examples

$\cos^{2} (t) - \sin^{2} (t)$

Step 1

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = \cos (t)$ and $b = \sin (t)$ .

$(\cos (t) + \sin (t)) (\cos (t) - \sin (t))$