(a+b-c)(a+b+c)-[(a- b)^2+4ab]
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/11 16:08:10
![(a+b-c)(a+b+c)-[(a- b)^2+4ab]](/uploads/image/z/15083392-40-2.jpg?t=%28a%2Bb-c%29%28a%2Bb%2Bc%29-%5B%28a-+b%29%5E2%2B4ab%5D)
x)HNMQɚ
IqF&I6IETِnTgUN3RU0lm8TX˓KXtOӵ醍f_\gr zG
(a+b-c)(a+b+c)-[(a- b)^2+4ab]
(a+b-c)(a+b+c)-[(a- b)^2+4ab]
(a+b-c)(a+b+c)-[(a- b)^2+4ab]
(a+b-c)(a+b+c) = (a+b)^2-c^2
(a- b)^2+4ab = a^2 - 2ab + b^2 + 4ab = (a+b)^2
两个式子相减就是-c^2