2道不定积分的题∫(e^x-1)^1/2dx∫coslnxdx
问题描述:
2道不定积分的题
∫(e^x-1)^1/2dx
∫coslnxdx
答
1.∫(e^x-1)^1/2dx 设(e^x-1)^1/2=t t^2=e^x-1,x=ln(t^2+1) ∫(e^x-1)^1/2dx =∫tdln(t^2+1) =∫2t^2/(t^2+1)dt =∫(2t^2+2-2)/(t^2+1)dt =2-2∫1/(t^2+1)dt+C =2-2arctan(t) +C =2-2arctan[(e^x-1)^1/2] +C 2.∫c...