Question

高数，积分怎么计算

Answer 1

如图

Answer 2

∫1/(1+√x)dx
令√x=t，则x=t²，dx=2tdt
原式=∫[2t/(1+t)]dt
=2∫[t/(1+t)]dt
=2∫[(1+t)-1]/(1+t)dt
=2∫[1-1/(1+t)]dt
=2[∫dt-∫(1/1+t)dt]
=2[t-ln|1+t|]+C
=2[√x-ln|1+√x|]+C