Chrome，
QQ浏览器
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![人教A高中数学必修四2.4.1 平面向量数量积的物理背景及其含义[王丽娜]【市一等奖】优质课](//imgshow.1ydt.com/img?url=%2F%2Fi2.hdslb.com%2Fbfs%2Farchive%2Fef3ec3fcc83f42203339af1a9ec2d6569c74d6bc.jpg%40672w_378h_1c_%21web-search-common-cover)
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播放：24 时间：2024-06-19简介： -
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![人教A高中数学必修四2.4.1 平面向量数量积的物理背景及其含义[王丽娜]【市一等奖】优质课](http://imgshow.1ydt.com/img?url=%2F%2Fi2.hdslb.com%2Fbfs%2Farchive%2Fef3ec3fcc83f42203339af1a9ec2d6569c74d6bc.jpg%40672w_378h_1c_%21web-search-common-cover)
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