(1+123+234)×(123+234+345)-(1+123+234+345)×(123+234)

来源:学生作业帮助网 编辑:六六作业网 时间:2024/07/05 11:52:37
(1+123+234)×(123+234+345)-(1+123+234+345)×(123+234)(1+123+234)×(123+234+345)-(1+123+234+345)×(123+23

(1+123+234)×(123+234+345)-(1+123+234+345)×(123+234)
(1+123+234)×(123+234+345)-(1+123+234+345)×(123+234)

(1+123+234)×(123+234+345)-(1+123+234+345)×(123+234)
设123+234为a,
则原式=(1+a)(345+a)-(346+a)a
=345+a+345a+a平方-346a-a平方
=345