Concept:Use the identity 1+sinx=(sin2x+cos2x)2 to simplify the integrand, then integrate and rewrite the result as a single sine function.Explanation:We know sin22x+cos22x=1 and 2sin2xcos2x=sinx.So 1+sinx=(sin2x+cos2x)2.Taking the positive square root, 1+sinx=sin2x+cos2x.Integrate:∫(sin2x+cos2x)dx=−2cos2x+2sin2x+C=2(sin2x−cos2x)+C.Use the identity sinA−cosA=2sin(A−4π) with A=2x.Then 2(sin2x−cos2x)=22sin(2x−4π).Therefore ∫1+sinxdx=22sin(2x−4π)+C.Answer:Option A: 22sin(2x−4π)+c