﹙1+0.112+0.123﹚×﹙0.112+0.123+0.134﹚-﹙1+0.112+0.123+0.134﹚×﹙0.112+_数学解答

﹙1+0.112+0.123﹚×﹙0.112+0.123+0.134﹚-﹙1+0.112+0.123+0.134﹚×﹙0.112+0.123﹚简便计算
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人气：145 ℃　时间：2020-04-12 17:05:26

解答

设 0.112+0.123=a
原式=﹙1+a﹚×﹙a+0.134﹚-﹙1+a+0.134﹚×a
=a+a²+0.134a+0.134 - (a+a²+0.134a)
=0.134