这个题是等于无穷吗?lim(x-->0)(1-cosx^2)/(sin^2xtan^2x)
问题描述:
这个题是等于无穷吗?lim(x-->0)(1-cosx^2)/(sin^2xtan^2x)
答
1-cosx^2 ~ 1/2*(x^2)^2 = 1/2*x^4
sin^2xtan^2x ~ x^2*x^2 = x^4
所以原式=1/2
答
lim(1-cosx²)/(sin²xtan²x)
=lim2sin²(x²/2) / (x²*x²)
=2lim (x²/2)²/x^4
=1/2