求不定积分∫1⼀(x+根号(1-x^2))dx?

答案是1/2(arcsinx+ln|x+根号(1-x^2)|)+C 求过程
2024-11-06 06:15:49
推荐回答(1个)
回答1:

∫dx/[x+√(1-x^2)]
令x=sint
原式=∫cost/(sint+cost) dt
=1/2 ∫(cost-sint)/(sint+cost) dt+1/2 ∫(cost+sint)/(sint+cost) dt
=1/2∫1/(sint+cost) d(sint+cost)+1/2∫dt
=1/2ln|sint+cost|+1/2t+c
t=arcsinx
cost=√1-x^2
所以
原式=1/2ln|x+√(1-x^2)|+1/2arcsinx+C