求下列函数的极限,需详细过程
1个回答
展开全部
lim(x→∞)[(x-1)/(x+1)]^x
=lim(x→∞)[(x+1-2)/(x+1)]^x
=lim(x→∞)[1-2/(x+1)]^x
=lim(x→∞){1+1/[(x+1)/(-2)]}^x
=lim(x→∞)【{1+1/[(x+1)/(-2)]}^[(x+1)/(-2)]】^(-2)
=e^(-2)
=lim(x→∞)[(x+1-2)/(x+1)]^x
=lim(x→∞)[1-2/(x+1)]^x
=lim(x→∞){1+1/[(x+1)/(-2)]}^x
=lim(x→∞)【{1+1/[(x+1)/(-2)]}^[(x+1)/(-2)]】^(-2)
=e^(-2)
追问
能解释下解题第一步的x+1-2是怎么变成第二步的1-2的吗?谢谢
追答
再写详细一点(同分母加减)(x+1-2)/(x+1)=[(x+1)-2]/(x+1)=[(x+1)/(x+1)]-[2/(x+1)]=1-[2/(x+1)]
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