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用乘法分配律算(2+1.33+2.9)×(1.33+2.9+3.14)-(2+1.33+2.9+3.14)×(1.33+2.9)

题目详情
用乘法分配律算
(2+1.33+2.9)×(1.33+2.9+3.14)-(2+1.33+2.9+3.14)×(1.33+2.9)
▼优质解答
答案和解析
设A=1.33+2.9 B=1.33+2.9+3.14
(2+1.33+2.9)×(1.33+2.9+3.14)-(2+1.33+2.9+3.14)×(1.33+2.9)
=(2+A)×B-(2+B)×A
=2B+AB-2A-AB
=2(B-A)
=2(1.33+2.9+3.14-1.33-2.9)
=6.28