Question

If cos 30 =2 cos square 15 -1 then cos 15 is ​

Answer 1

Answer:

cos 30 =2 cos square 15 - 1

$\frac{ \sqrt{3} }{2} - 1 = 2 {cos}^{2} 15 \\ \frac{ \sqrt{3} - 2 \ }{4} = {cos}^{2} 15 \\ then \\ \\ cos15 = \frac{ \sqrt{ \sqrt{3} - 2 } }{2}$

HOPE IT HELPS YOU

Answer 2

Answer:

Step-by-step explanation:

I don't know the answer