Question

Find ϴ in the equation sin(ϴ + 15) = cos(2ϴ)

a. 50
b. 75
c. 25
d. 40

Answer 1

the answer is c. 25

sin(ϴ + 15) = cos(2ϴ)
sin(ϴ + 15) =sin(25 + 15) =sin(40) =0.64
cos(2ϴ)=cos(2x25)=cos(50)=0.64
so ϴ=25