Question

If sin∅=12/13, what is the value of cos2∅ ​

Answer 1

-0.7046

Explanation:

sin∅ = 12/13

∅ = sin⁻¹(12/13) = 67.38⁰

cos(2)(67.38) = -0.7046

The cosine is negative because 2 x 67.38 = 134.76, which is an obtuse angle