(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34的简便算是多少

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(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34的简便算是多少

(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34的简便算是多少
(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34的简便算是多少

(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34的简便算是多少
1、这道题要用“假设法”来做.
2、假设:1+0.23+0.34=a; 0.23+0.34=b;
(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34)
=a×(b+0.65)-(a+0.65)×b
=ab+0.65a-ab-0.65b
=0.65×(a-b)…………因为:a=1+0.23+0.34;b=0.23+0.34
=0.65×(1+0.23+0.34-0.23-0.34)
=0.65×1
=0.65

(1+0.23+0.34)*(0.23+0.34+0.65)-(1+0.23+0.34+0.65)*(0.23+0.34)
=(0.23+0.34+0.65)+(0.23+0.34)*(0.23+0.34+0.65)-(0.23+0.34)-(0.23+0.34)(0.23+0.34+0.65)
=0.65

令A=0.23+0.34=0.57
式子=(1+A)*(A+0.65)-(1+A+0.65)*A
=A+A2+0.65A+0.65-A-A2-0.65A
=0.65