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> 本节我们学习了定理:“直角三角形斜边上的中线等于斜边的一半。”即:如图①所示,在Rt△ABC中,∠ACB=90°,若CD是斜边AB上的中线,则有CD=AB。证明这个定理的方法有多种,教材是-八年级数
本节我们学习了定理:“直角三角形斜边上的中线等于斜边的一半。”即:如图①所示,在Rt△ABC中,∠ACB=90°,若CD是斜边AB上的中线,则有CD=AB。证明这个定理的方法有多种,教材是-八年级数
题目简介
本节我们学习了定理:“直角三角形斜边上的中线等于斜边的一半。”即:如图①所示,在Rt△ABC中,∠ACB=90°,若CD是斜边AB上的中线,则有CD=AB。证明这个定理的方法有多种,教材是-八年级数
题目详情
本节我们学习了定理:“直角三角形斜边上的中线等于斜边的一半。”即:
如图①所示,在Rt △ABC中,∠ACB=90°,若CD 是斜边AB上的中线,则有CD=
AB。证明这个定理的方法有多种,教材是利用矩形的性质进行证明的,其实还可利用三角形的中位线定理来证明,请你根据图中已添的辅助线证明此定理。
(1)方法(一):如图②所示,延长BC至E,使CE=BC,连结AE;
(2 )方法(二):如图③所示,取BC的中点E,连结DE。
题型:解答题
难度:中档
来源:同步题
答案
解“略”。
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直角三角形中斜边上的中线长为
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题目简介
本节我们学习了定理:“直角三角形斜边上的中线等于斜边的一半。”即:如图①所示,在Rt△ABC中,∠ACB=90°,若CD是斜边AB上的中线,则有CD=AB。证明这个定理的方法有多种,教材是-八年级数
题目详情
如图①所示,在Rt △ABC中,∠ACB=90°,若CD 是斜边AB上的中线,则有CD=
(1)方法(一):如图②所示,延长BC至E,使CE=BC,连结AE;
(2 )方法(二):如图③所示,取BC的中点E,连结DE。
答案