题目
题型:不详难度:来源:
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答案
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∴(
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|2
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设
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则cosθ=
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2
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则θ=arccos
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核心考点
试题【已知|a=2,|b|=1,a与b的夹角为60°,求向量.a+2b与2a+b的夹角.】;主要考察你对平面向量模和夹角的坐标表示等知识点的理解。[详细]
举一反三
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(
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