求积分∫ 1/(1+e^2x) dx
1个回答
展开全部
设t=e^(2x),x=(lnt)/2,dx=1/(2t) dt
∫dx/[1+e^(2x)]
= (1/2)∫dt/[t(1+t)]
= (1/2)∫[(1+t)-t]/[t(1+t)] dt
= (1/2)∫[1/t - 1/(1+t)] dt
= (1/2)[ln|t| - ln|1+t|] + C
= (1/2)[ln|e^(2x)| - ln|1+e^(2x)] + C
= x - (1/2)ln|1+e^(2x)| + C
∫dx/[1+e^(2x)]
= (1/2)∫dt/[t(1+t)]
= (1/2)∫[(1+t)-t]/[t(1+t)] dt
= (1/2)∫[1/t - 1/(1+t)] dt
= (1/2)[ln|t| - ln|1+t|] + C
= (1/2)[ln|e^(2x)| - ln|1+e^(2x)] + C
= x - (1/2)ln|1+e^(2x)| + C
已赞过
已踩过<
评论
收起
你对这个回答的评价是?
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询