Gaokao Math Practice Question
在 $\triangle A B C$ 中, $\cos C=\frac{2}{3}, A C=4, B C=3$, 则 $\cos B=(\qquad)$
- A.$\frac{1}{9}$
- B.$\frac{1}{3}$
- C.$\frac{1}{2}$
- D.$\frac{2}{3}$
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