lim(1-根号cosx/x^2 )=lim((x^2-根号cosx)/x^2 )
罗比他法则对分子分母求导=lim((2x+1/2sinx/根号cosx)/2x )
=lim((2+1/2(cosx根号cosx-sinx/根号cosx)/cosx)/2 )
=5/4
lim(1-根号cosx/x^2 )=lim((x^2-根号cosx)/x^2 )
罗比他法则对分子分母求导=lim((2x+1/2sinx/根号cosx)/2x )
=lim((2+1/2(cosx根号cosx-sinx/根号cosx)/cosx)/2 )
=5/4