[x*sin(3/x)]的极限,x趋于正无穷

题目

[x*sin(3/x)]的极限,x趋于正无穷

答案

lim(x→∞)x*sin(3/x)
t=1/x
=lim(t→0)sin(3t)/t=lim(t→0)3sin(3t)/(3t)=3