Question

求极限，怎么求，详细过程，谢谢

Answer 1

分子分母同时乘以
√(x+1)+1
分子可以变成x
【平方差公式】

原式=lim(x→0)1/[√(x+1)+1]
=1/[√(0+1)+1]
=1/2

Answer 2

This improper integral can be evaluated by A、substitution（reciprocal substitution）, B、integral by parts，and C、L'Hopital's rule. . The detailed solution is as follows for your reference. . . .。