If∫1sin(x−a)sin(x−b)dx =A logsin(x-a)sin(x-b)+c
sin(a-b)
Sin(b-a)
cosec(b-a)
cosec(a-b)
∫1sin(x−a)sin(x−b)dx=1sin(a−b)∫sin{(x−b)−(x−a)}sin(x−a)sin(x−b)dx =1sin(a−b)∫sin(x−b)cos(x−a)−cos(x−b)sin(x−a)sin(x−a)sin(x−b)dx=1sin(a−b)∫{cot(x−a)−cot(x−b)}dx=1sin(a−b){log|sin(x−a)|−log|sin(x−b)|}+c=cosec(a−b)logsin(x−a)sin(x−b)+c