Question

Prove that sine square (π/8+A/2) -sun square (π/8-A/2)=1/√2 sinA answer

Answer 1

Answer:

Using

sin

2

A−sin

2

B=sin(A+B)sin(A−B)

we get

LHS =sin(π/8+A/2+π/8−A/2)sin(π/8+A/2−π/8−A/2)=sin(π/4)sinA=(1/

2

)sinA= RHS