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关于数学的问题
在角ABC中，三边长分别为abc，试化简a+b-c的绝对值减b-a-c的绝对值=
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沙发#
发布于：2013-09-11 15:19
帮帮忙
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板凳#
发布于：2013-09-11 16:13
三角形两边之和大于第三边，∴ (a+b)＞c
三角形两边之差小于第三边，∴ (b-a)＜c ∴| a+b-c | - | b-a-c | = | (a+b)-c | - | (b-a)-c | = (a+b)-c - {c- (b-a) } = a+b-c - c+b-a = 2b-2c |
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地板#
发布于：2013-09-11 16:37
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