>>622
>>617の続き
z = (x^y)/x = x^(y-1)
とおく
log(z) = (y-1)log(x)
x→ + 0 で これも不定形
lim log(z) = lim (y-1)log(x) = lim ((log(x))/(1/(y-1))
= （ロピタル）
= lim (-(y-1)^2)/(x y') = - lim ((y-1)^2)/(x y (1+log(x))
= - lim ((y-1)^2)/(x (1+log(x))
= （ロピタル）
= - lim (2(y-1)y')/((1+log(x))+1)
= - 2 lim ((y-1)y (1+log(x)))/((1+log(x))+1)
= - 2 lim (y-1) /((1+{1/(1+log(x))}) = 0

したがって、z → 1