lim(tanx-x)/( sinx-x )=?(x趋向于0)
问题描述:
lim(tanx-x)/( sinx-x )=?(x趋向于0)
答
利用泰勒展开式求极限
lim【x→0】(tanx-x)/(sinx-x)
=lim【x→0】[x+(x^3)/3+o(x^3)-x]/[x-(x^3)/3!+o(x^3)-x]
=lim【x→0】[(x^3)/3+o(x^3)]/[-(x^3)/6+o(x^3)]
=-2
答案:-2