Question

find the extreme value of Cos2x+Cos square x​

Answer 1

Step-by-step explanation:

Cos2x + Cos²x

Cos²x - Sin²x + Cos²x

2Cos²x - Sin²x

Answer 2

Answer:

2

Step-by-step explanation:

cosx has its maximum value when x=0

i.e., cos0=1

similarly cos2x has its maximum value when x=0, cos(2×0)=cos0=1

Therefore, Cos2x + cosx will have its maximum value when x=0

cos0+cos0= 1+1 =2