例题解析初中数学最经典的9大解题方法,贯穿三年都能用!
发布于 2021-04-01 23:54 ,所属分类:在线教育信息快讯
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中学数学好教师
资源干货,数学趣味,每天八点半,每天10分钟,提高中学数学教学力、学习力!
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证明:
则S△ABC=S△ABD+S△ACD,即
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∴CG=DE+DF
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