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#b68100ff-e629-45ad-96ce-c965551add91中等解答题向量的数量积平面向量

37. 已知a=(cosα,sinα)\overrightarrow{a}=(\cos \alpha ,\sin \alpha )b=(cosβ,sinβ)\overrightarrow{b}=(\cos \beta ,\sin \beta )0<β<α<π0<\beta <\alpha <\pi
(1)若ab=2\vert \overrightarrow{a}-\overrightarrow{b}\vert =\sqrt{2},求证:ab\overrightarrow{a}\bot \overrightarrow{b}
(2)设c=(0,1)\overrightarrow{c}=(0,1),若a+b=c\overrightarrow{a}+\overrightarrow{b}=\overrightarrow{c},求α\alphaβ\beta的值.