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已知\(\vartriangle ABC\)中,角\(A{\rm{ }},B{\rm{ }},C\)的对边分别为\(a{\rm{ }},b{\rm{ }},c\),若\(2b\cos C - 2c\cos B = a\),\(b = \sqrt 2 c\),则\(\cos C = \)( ).
A.\(\frac{3}{4}\)
B.\(\frac {3} {5}\)
C.\(\frac {2} {5}\)
D.\(\frac {1} {4}\)
参考答案:A
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