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问题:

()22×98 (2)2 2

答案:

解: ()22×98 =(2+2)(2﹣2) =2 2 ﹣2 2 =4﹣4 =3999; (2)2 2 =(+2) 2 = 2 +2××2+2 2 =+4+4 =44.