lim x→0 [sin6x+xf(x)]/x^3=0,求 lim x→0 [6+f(x)]/x^2
问题描述:
lim x→0 [sin6x+xf(x)]/x^3=0,求 lim x→0 [6+f(x)]/x^2
答
因为lim x→0 [sin6x/(6x)]=1
所以,
lim x→0 [sin6x+xf(x)]/x^3
=lim x→0 [6x+xf(x)]/x^3
=lim x→0 [6+f(x)]/x^2
=0