令0.12+0.23+0.34=a 则0.14+0.23=a-0.32
原式=(1+a)× a -(1+a)×(a-0.32)
=(a + a的平方)-(a - 0.32 + a的平方 - 0.32a)
=0.32×(1+a)
=0.32×(1+0.12+0.23+0.34)
=0.32×1.69
-0.5408
令0.12+0.23+0.34=a 则0.14+0.23=a-0.32
原式=(1+a)× a -(1+a)×(a-0.32)
=(a + a的平方)-(a - 0.32 + a的平方 - 0.32a)
=0.32×(1+a)
=0.32×(1+0.12+0.23+0.34)
=0.32×1.69
-0.5408