求解,[(1+x)∧(1⼀x)-e]⼀x当x→0时的极限。

2025-05-09 09:28:17
推荐回答(1个)
回答1:

lim(x->0)[(1+x)^(1/x)-e]/x (用罗比达法则)
=lim(x->0)[(1+x)^(1/x)][(1/x)/(x+1)-ln(x+1)/x²]/1
=lim(x->0)[(1+x)^(1/x)][x-(x+1)ln(x+1)]/[x²(1+x)]
=(x->0)lim[(1+x)^(1/x)]*lim{[x-(x+1)ln(x+1)]/[x²(1+x)]}
=(x->0)e*lim{[x-(x+1)ln(x+1)]/[x²(1+x)]}(用罗比达法则)
=(x->0)e*lim{[1-ln(x+1)-1]/[2x(1+x)+x²]}
=(x->0)e*lim{[-ln(x+1)]/[3x²+2x]} (用罗比达法则)
=(x->0)e*lim{[-1/(x+1)]/[6x+2]}
=(x->0)e*lim{-1/[2(x+1)(3x+1)]}
=e*{-1/[2(1)(1)]}
= -e/2