lim(x趋向0)(1-cos2x)/xsinx怎么解?
问题描述:
lim(x趋向0)(1-cos2x)/xsinx怎么解?
答
lim(x趋向0)(1-cos2x)/xsinx
=lim(x趋向0)[(1-1+2Sin^2(x)] /xsinx
=lim(x趋向0)2sin^2x/xsinx
=lim(x趋向0)2sinx/x
=2