Question

Solve Cos' (Cos 3pie /6)​

Answer 1

Answer:

cos[cos

−1

(

2

−

3

)+

6

π

]

=cos[cos

−1

(cos

6

5π

)][∵cos

6

5π

=

2

−

3

]

=cos(

6

5π

+

6

π

){cos

−1

cosx=x,x∈[0,π]}

=cos(

6

6π

)

=cos(π)=−1