Question

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• A£® ÈôAB=BC£¬AC¶Îƽ¾ùËÙ¶ÈΪ$\frac{{v}_{1}+{v}_{2}}{2}$
• B£® ÈôAB=BC£¬AC¶Îƽ¾ùËÙ¶ÈΪ$\sqrt{\frac{{{v}_{1}}^{2}+{{v}_{2}}^{2}}{2}}$
• C£® Èôt₁=t₂£¬AC¶Îƽ¾ùËÙ¶ÈΪ$\frac{{v}_{1}+{v}_{2}}{2}$
• D£® Èôt₁=t₂£¬AC¶Îƽ¾ùËÙ¶ÈΪ$\frac{2{v}_{1}{v}_{2}}{{v}_{1}+{v}_{2}}$

Answer 1

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