Question

求极限，要过程！

Answer 1

原式=lim<x→0>[(x/5)/sin(x/5)]²×25
=1²×25
=25

Answer 2

x->0
(sin(x/5))^2 ~ (1/25)x^2

lim(x->0) x^2/(sin(x/5))^2
=lim(x->0) x^2/[(1/25)x^2]
=25