来自刘利华的问题
数学题三角函数已知2sin(3π+θ)=cos(π+θ),求2sin^2θ+3sinθcosθ-cos^2θ
数学题三角函数
已知2sin(3π+θ)=cos(π+θ),求2sin^2θ+3sinθcosθ-cos^2θ
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2020-11-06 17:33
数学题三角函数已知2sin(3π+θ)=cos(π+θ),求2sin^2θ+3sinθcosθ-cos^2θ
数学题三角函数
已知2sin(3π+θ)=cos(π+θ),求2sin^2θ+3sinθcosθ-cos^2θ
2sin(3π+θ)=cos(π+θ)2sinθ=cosθtanθ=1/22sin^2θ+3sinθcosθ-cos^2θ2sin^2θ+3sinθcosθ-cos^2θ___________________________=____________________________=1...