Question

cos 2A=sin40 then find the measure of angle A​

Answer 1

Answer:

cos2A= sin40

sin(90-2A)=sin40

90-2A=40

-2A=40-90=-50

A=-50/-2=25

Answer 2

Answer:

cos 2A=sin 40

cos2A=cos (90-40)

cos 2A=cos 50

2A=50

A=25°