Question

sin2 pi /4- x + sin2 pi/4+x = ?​

Answer 1

Step-by-step explanation:

Let f(x)=sin(

4

π

−x)sin(

4

π

+x)

=

2

cos(2x)−cos(

2

π

)

[2sinAsinB=cos(A−B)−cos(A+B)]

f(x)=

2

cos2x

[cos

2

π

=0]

∴ Period of f(x)=

2

2π

=π

[If Period of f(x) is T, then Period of f(kx) is

∣k∣

T

]