IIT JEE , AIEEE Forum - Mathematics , Integral Calculus - jst integrate sin x /sin 4x w.r.t. x.......

P90

sinx/sin4x = (sinx)/(4sinxcosx * cos2x)

sinx in num and denom go away...

then it is integral(dx/4cosx*cos2x)

express 1/cosx as (cosx)/(cosx)²

^{_{then it is integral(cosx dx/(cos}2_x)(1-2sin2_x)}

_{^{put sinx=t then cosxdx=dt}}

_{^{then finish it off with partial fractions......which no doubt is boring}}