lim(x→0)(1-cosx)/(xsinx)=?
问题描述:
lim(x→0)(1-cosx)/(xsinx)=?
答
lim(x→0)(1-cosx)/(xsinx)
=lim(x→0)(1-(1-2(sin x/2)^2)/(xsinx)
=(1-(1-2*x^2*(1/2)^2))/x^2
=1/2