sinΘ-cosΘ=1/2,求tanΘ+cotΘ
问题描述:
sinΘ-cosΘ=1/2,求tanΘ+cotΘ
答
与sinx + cosx = 0/5
(与sinx + cosx)^ 2 = 16/25
1 +2 sinxcosx = 16/25
sinxcosx = -9/50
氮化钽+ cotx = sinx的/ cosx + cosx / sinx的= {(与sinx)^ 2 +(cosx)^ 2} /(sinxcosx)= 1 /(-9/50)= -50 / 9
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答
解sinθ-cosθ=1/2两边平方得:sin²θ-2sinθcosθ+cos²θ=1/4即1-2sinθcosθ=1/4∴sinθcosθ=3/8∴tanθ+cotθ=(sinθ/cosθ)+(cosθ/sinθ)=(sin²θ+cos²θ)/(sinθcosθ)=1/(3/8)=8/3...