一道关于用洛必达法则求极限的题求lim(x->π)(π-x)tan(x/2)这道题我死活求出来都是一无穷大~我的具体步骤是:lim(x->π)(π-x)tan(x/2) = lim(x->π)tan(x/2) / [1/(π-x)] =(∞/∞不定式)lim(x->π)sec^2(x/2) / 1 = l

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一道关于用洛必达法则求极限的题求lim(x->π)(π-x)tan(x/2)这道题我死活求出来都是一无穷大~我的具体步骤是:lim(x->π)(π-x)tan(x/2) = lim(x->π)tan(x/2) / [1/(π-x)] =(∞/∞不定式)lim(x->π)sec^2(x/2) / 1 = l

一道关于用洛必达法则求极限的题求lim(x->π)(π-x)tan(x/2)这道题我死活求出来都是一无穷大~我的具体步骤是:lim(x->π)(π-x)tan(x/2) = lim(x->π)tan(x/2) / [1/(π-x)] =(∞/∞不定式)lim(x->π)sec^2(x/2) / 1 = l
一道关于用洛必达法则求极限的题
求lim(x->π)(π-x)tan(x/2)
这道题我死活求出来都是一无穷大~我的具体步骤是:
lim(x->π)(π-x)tan(x/2) = lim(x->π)tan(x/2) / [1/(π-x)] =(∞/∞不定式)lim(x->π)sec^2(x/2) / 1 = lim(x->π) 1/cos^2(x/2) = ∞
书后的答案是2
我不知道我错在哪里,难道这题不该先化成不定式吗,还是我解题过程中的某个地方错了?

一道关于用洛必达法则求极限的题求lim(x->π)(π-x)tan(x/2)这道题我死活求出来都是一无穷大~我的具体步骤是:lim(x->π)(π-x)tan(x/2) = lim(x->π)tan(x/2) / [1/(π-x)] =(∞/∞不定式)lim(x->π)sec^2(x/2) / 1 = l
你分母的求导不对啊.
lim(x->π)(π-x)tan(x/2) = lim(x->π)tan(x/2) / [1/(π-x)]
=L'H lim(x->π) [(π-x)^2]/(cosx+1)
=L'H 2lim(x->π) (π-x)/sinx
=L'H 2lim(x->π) (-1)/cosx
=2