qiputang
幼苗
共回答了20个问题采纳率:95% 举报
8.原式=lim(x->0)(sec²x-1)/(1-cosx)
=lim(x->0)(tan²x)/(x²/2)
=lim(x->0)(x²)/(x²/2)
=2
10)所以=lim(x->0)(1-cosx+xsinx)/(1-cosx)
=lim(x->0)(sinx+sinx+xcosx)/(sinx)
=lim(x->0)(2sinx+xcosx)/(sinx)
=lim(x->0)(2sinx)/sinx+lim(x->0)(xcosx)/(sinx)
=2+lim(x->0)(xcosx)/(x)
=2+1
=3
1年前
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