✔ 最佳答案
lim x->∞ [(x + 1) / (x - 1)]^(x + 1)
= lim x->∞ [1 + 2 / (x - 1)]^(x - 1 + 2)
= lim x->∞ [1 + 2 / (x - 1)]^(x - 1)[1 + 2 / (x - 1)]^2
= {lim x->∞ [1 + 2 / (x - 1)]^(x - 1)}{lim x->infinity[1 + 2 / (x - 1)]^2}
= (e^2)(1)
= e^2
lim x->∞ [x^2 / (x^2 - 1)]^x
= lim x->∞ [x^2 / (x^2 - 1)]^(x^2 - 1 + 1)/x
= lim x->∞ [1 + 1 / (x^2 - 1)]^(x^2 - 1)/x[1 + 1 / (x^2 - 1)]^(1/x)
= {lim x->∞ [1 + 1 / (x^2 - 1)]^(x^2 - 1)/x}{lim x->∞[1 + 1 / (x^2 - 1)]^(1/x)}
= lim x->∞ {[1 + 1 / (x^2 - 1)]^(x^2 - 1)}^(1/x){1^0}
= lim x->∞ {e}^(1/x)
= e^0
= 1