若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )A.6 B.4 C.2 D.0亲,麻烦写出详细的步骤,谢谢!
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![若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )A.6 B.4 C.2 D.0亲,麻烦写出详细的步骤,谢谢!](/uploads/image/z/1746962-26-2.jpg?t=%E8%8B%A5%28sin%26%23178%3B%CE%B8%2B4%29%2F%28cos%CE%B8%2B1%29%3D2%2C%E5%88%99%28cos%CE%B8%2B2%29%28cos%CE%B8%2B1%29%E7%9A%84%E5%80%BC%E4%B8%BA%28+%29%E8%8B%A5%28sin%26%23178%3B%CE%B8%2B4%29%2F%28cos%CE%B8%2B1%29%3D2%2C%E5%88%99%28cos%CE%B8%2B2%29%28cos%CE%B8%2B1%29%E7%9A%84%E5%80%BC%E4%B8%BA%28+++++++%29A.6++++++++++++++++B.4++++++++++++++++++++C.2+++++++++++++++++++D.0%E4%BA%B2%2C%E9%BA%BB%E7%83%A6%E5%86%99%E5%87%BA%E8%AF%A6%E7%BB%86%E7%9A%84%E6%AD%A5%E9%AA%A4%2C%E8%B0%A2%E8%B0%A2%21)
若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )A.6 B.4 C.2 D.0亲,麻烦写出详细的步骤,谢谢!
若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )
若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )
A.6 B.4 C.2 D.0
亲,麻烦写出详细的步骤,谢谢!
若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )若(sin²θ+4)/(cosθ+1)=2,则(cosθ+2)(cosθ+1)的值为( )A.6 B.4 C.2 D.0亲,麻烦写出详细的步骤,谢谢!
(sin²θ+4)/(cosθ+1)=2
sin²θ+4=2(cosθ+1)
1-cos²θ+4=2cosθ+2
cosθ¹+2cosθ-3=0
(cosθ+3)(cosθ-1)=0
cosθ∈[-1,1],故cosθ+3≠0,
cosθ-1=0,cosθ,=1
故结果是6
如有不明白,可以追问.如有帮助,记得采纳,谢谢
A 让cosθ=x (1-x2+4)/(x+1)=2