Question

求极限的题

求极限的题这个题怎么求，大神们

Answer 1

追问

中括号里面的是等价代换吗，还没上大学

Answer 2

(x+c)/(x-c) = 1 + 2c/(x-c)
let
1/y = 2c/(x-c)
lim(x-> ∞) [(x+c)/(x-c) ]^x
=lim(x-> ∞) [1 + 2c/(x-c) ]^x
=lim(y-> ∞) [1 + 1/y ]^[2cy+c]
=lim(y-> ∞) [1 + 1/y ]^(2cy)
=e^(2c)