问题标题:
数学题三角函数已知2sin(3π+θ)=cos(π+θ),求2sin^2θ+3sinθcosθ-cos^2θ
问题描述:

数学题三角函数

已知2sin(3π+θ)=cos(π+θ),求2sin^2θ+3sinθcosθ-cos^2θ

郭建星回答:
  2sin(3π+θ)=cos(π+θ)2sinθ=cosθtanθ=1/22sin^2θ+3sinθcosθ-cos^2θ2sin^2θ+3sinθcosθ-cos^2θ___________________________=____________________________=1...
查看更多
数学推荐
热门数学推荐