在邊長為的正三角形ABC中，設(shè)，則等于（ ）

A．0 B．1 C．3 D．－3

D

解析試題分析：∵三角形ABC為邊長為的正三角形，∴，故選D
考點(diǎn)：本題考查了數(shù)量積的運(yùn)用
點(diǎn)評：熟練掌握向量的夾角及數(shù)量積的定義是解決此類問題的關(guān)鍵，屬基礎(chǔ)題

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