中考数学专题复习:三角?- 百度文库

ʱ : 中考数学专题复习:三角?- 百度文库ϿʼĶ

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A1 B2 C3 D4

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ıȵ һ߶ 1 ͼ֪ABCAB=AC=1A=36㣬ABCƽBDACڵDADij cosAֵ ţ Ӧѵ 2ͼڡABCУAB=ACA=36㣬BDƽ֡ABCACڵDAC=2ADijǣ A

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