Question

What is equal to 2cos²45=

Answer 1

Step-by-step explanation:

$cos45 = \frac{1}{ \sqrt{2} }$

$2 {cos}^{2} 45 = 2 \times ( \frac{1}{ \sqrt{2} } ) {}^{2}$

$2 {cos}^{2} 45 = 2 \times \frac{1}{2}$

$2 {cos}^{2} 45 = 1$