高数,极限问题,求大神解答...

∵x→0时,1-cosx~x²/2
∴1-cos√x x/2
lim [1- √(cosx) ] / [x(1- cos√x )]
= lim [1- √(cosx)] / (x²/2)
= lim [1-√(cosx)][1+√cosx] / (x²/2)[1+√cosx]
= lim (1- cosx) / (x²/2)(1+√cosx) ...展开全文你好!
∵x→0时,1-cosx~x²/2
∴1-cos√x x/2
lim [1- √(cosx) ] / [x(1- cos√x )]
= lim [1- √(cosx)] / (x²/2)
= lim [1-√(cosx)][1+√cosx] / (x²/2)[1+√cosx]
= lim (1- cosx) / (x²/2)(1+√cosx)
= lim (x²/2) / (x²/2)(1+√cosx)
= 1/2收起