Question

Simplify cos^2 44degrees - sin^2 44 degrees by using double-angle formula?

Answer 1

`cos(88°)`

Explanation:

Cos double angle formula:
`cos2theta= cos^2theta-sin^2theta`

So in this case let `theta` be `44` degrees
`cos^2(44°)- sin^2(44°)=`
`cos(2*44°)=`
`cos(88°)`