求解积分∫(1+x²)^1/2 dx

求解积分∫(1+x²)^1/2 dx
求解积分∫(1+x²)^1/2 dx

求解积分∫(1+x²)^1/2 dx
http://zhidao.baidu.com/link?url=SerUUXOmWUWiusDP16YYZTnxyQDBsPlDXt1OKcdhiOYN5dn64FqqGz5jBQM5Fb5tE0xetMVNYwqRpjK9AN_QQ_

令x=tana
dx=sec^2 ada
原式=∫tana*sec^2 ada
=∫sinada/cos^3a
=-∫(cosa)^-3dcosa
=-(cosa)^-2/(-2)+C
=(seca)^2/2+C
=(x^2+1)/2+C