化简:[(1+sinθ+cosθ)(sinθ/2-cosθ/2)]/√(2+2cosθ)(0<θ<π)=[2sin(θ/2)cos(θ/2)+2cos²(θ/2)](sinθ/2-cosθ/2)=2cos(θ/2)(sinθ/2+cosθ/2)(sinθ/2-cosθ/2)我分子已经算到这儿了 而且分母不会化简
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/08 23:25:21
![化简:[(1+sinθ+cosθ)(sinθ/2-cosθ/2)]/√(2+2cosθ)(0<θ<π)=[2sin(θ/2)cos(θ/2)+2cos²(θ/2)](sinθ/2-cosθ/2)=2cos(θ/2)(sinθ/2+cosθ/2)(sinθ/2-cosθ/2)我分子已经算到这儿了 而且分母不会化简](/uploads/image/z/12435417-9-7.jpg?t=%E5%8C%96%E7%AE%80%EF%BC%9A%5B%281%2Bsin%CE%B8%2Bcos%CE%B8%29%28sin%CE%B8%2F2-cos%CE%B8%2F2%29%5D%2F%E2%88%9A%282%2B2cos%CE%B8%29%EF%BC%880%EF%BC%9C%CE%B8%EF%BC%9C%CF%80%EF%BC%89%3D%5B2sin%28%CE%B8%2F2%29cos%28%CE%B8%2F2%29%2B2cos%26%23178%3B%28%CE%B8%2F2%29%5D%28sin%CE%B8%2F2-cos%CE%B8%2F2%29%3D2cos%28%CE%B8%2F2%29%28sin%CE%B8%2F2%2Bcos%CE%B8%2F2%29%28sin%CE%B8%2F2-cos%CE%B8%2F2%29%E6%88%91%E5%88%86%E5%AD%90%E5%B7%B2%E7%BB%8F%E7%AE%97%E5%88%B0%E8%BF%99%E5%84%BF%E4%BA%86+%E8%80%8C%E4%B8%94%E5%88%86%E6%AF%8D%E4%B8%8D%E4%BC%9A%E5%8C%96%E7%AE%80)
化简:[(1+sinθ+cosθ)(sinθ/2-cosθ/2)]/√(2+2cosθ)(0<θ<π)=[2sin(θ/2)cos(θ/2)+2cos²(θ/2)](sinθ/2-cosθ/2)=2cos(θ/2)(sinθ/2+cosθ/2)(sinθ/2-cosθ/2)我分子已经算到这儿了 而且分母不会化简
化简:[(1+sinθ+cosθ)(sinθ/2-cosθ/2)]/√(2+2cosθ)(0<θ<π)
=[2sin(θ/2)cos(θ/2)+2cos²(θ/2)](sinθ/2-cosθ/2)
=2cos(θ/2)(sinθ/2+cosθ/2)(sinθ/2-cosθ/2)我分子已经算到这儿了 而且分母不会化简
化简:[(1+sinθ+cosθ)(sinθ/2-cosθ/2)]/√(2+2cosθ)(0<θ<π)=[2sin(θ/2)cos(θ/2)+2cos²(θ/2)](sinθ/2-cosθ/2)=2cos(θ/2)(sinθ/2+cosθ/2)(sinθ/2-cosθ/2)我分子已经算到这儿了 而且分母不会化简
原式=[(1+sinθ)+cosθ](sin θ/2 - cos θ/2) / √2(1+cosθ)
=[(sin θ/2 + cos θ/2)² + (cos θ/2 + sin θ/2)(cos θ/2 - sin θ/2)](sin θ/2 - cos θ/2) / √2×2cos² θ/2
(∵0<θ<π ,∴0<θ/2<π/2)
=[(cos...
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原式=[(1+sinθ)+cosθ](sin θ/2 - cos θ/2) / √2(1+cosθ)
=[(sin θ/2 + cos θ/2)² + (cos θ/2 + sin θ/2)(cos θ/2 - sin θ/2)](sin θ/2 - cos θ/2) / √2×2cos² θ/2
(∵0<θ<π ,∴0<θ/2<π/2)
=[(cos θ/2 + sin θ/2)(2cos θ/2)](sin θ/2 - cos θ/2) / (2cos θ/2)
=(cos θ/2 + sin θ/2)(sin θ/2 - cos θ/2)
=-(cos² θ/2 - sin² θ/2)
=-cosθ
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