在邊長(zhǎng)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(zhǎng)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(píng):熟練掌握向量的夾角及數(shù)量積的定義是解決此類問(wèn)題的關(guān)鍵,屬基礎(chǔ)題

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