Question
Question: If \(\int_{}^{}\frac{\sin x}{\sin(x - \alpha)}\)dx = Ax + B log sin (x – a) + c then value of (A, B)...
If ∫sin(x−α)sinxdx = Ax + B log sin (x – a) + c then value of (A, B) is
A
(– sin a, cos a)
B
(cos a, sin a)
C
(sin a, cos a)
D
(– cos a, sin a)
Answer
(cos a, sin a)
Explanation
Solution
∫sin(x−α)sin(x−α+α)dx
= ∫sin(x−α)sin(x−α)cosα+cos(x−α)sinα dx
= cos a ∫dx+sinα∫cot(x−α)dx= (cos a). x + sin a.
log {sin (x – a)} + c