Question

cos根号下x 的1/x次方在x→0时的极限等于?

Answer 1

原茄凳式=e^(lim(x--->0)(lncos根号下x)/x
=e^(lim(x--->0)1/(cos根号下x)*(-sin根号下x)*(1/2根号下x)
(x-->0,sin根号下x等价于根号下x）桐衫
=e^(lim(x--->0)(-1/(2cos根号下x))
=e^(-1/局纳腔(2cos0))
=1/根号e