Concept:Simplify the integrand using the identity cos2x=1−sin2x, then use substitution u=sinx.Explanation:Write cos3x=cosx⋅cos2x.Use cos2x=1−sin2x, so the numerator becomes (1−sin2x)cosx.The denominator is sin2x+sinx=sinx(sinx+1).So the integral is:∫sinx(sinx+1)(1−sin2x)cosxdxFactor the numerator: 1−sin2x=(1−sinx)(1+sinx).Cancel (1+sinx) from numerator and denominator:∫sinx1−sinxcosxdxLet u=sinx, then du=cosxdx.The integral becomes:∫u1−udu=∫(u1−1)duThis evaluates to log∣u∣−u+C.Substitute back u=sinx:log∣sinx∣−sinx+CThis matches Option B.Answer:Option B: log(sinx)−sinx+c, where c is the constant of integration.