∫(√1+e^x)dx

来源:学生作业帮助网 编辑:作业帮 时间:2024/07/20 05:44:21
∫(√1+e^x)dx
x}? 0ƯƖB27]<ĭ2:y{s3)|OH:е}{lW;m+uno@NA[=jJeue)i5(gVNjfG06*kJ00dBCj-Dž٣bt=!. 1a_[U <š<o

∫(√1+e^x)dx
∫(√1+e^x)dx

∫(√1+e^x)dx
令 √(1+e^x) = u, 则 e^x=u^2-1, x=ln(u^2-1), dx= 2udu/(u^2-1)
I = ∫ √(1+e^x)dx = ∫ 2u^2du/(u^2-1) = 2 ∫ [1+1/(u^2-1)]du
= 2u + ∫ [1/(u-1)-1/(u+1)]du = 2u + ln |(u-1)/(u+1)| + C
= 2√(1+e^x) + ln |[√(1+e^x)-1]/[√(1+e^x)+1)]| + C
= 2√(1+e^x) + 2ln[√(1+e^x)-1] - x + C