问题描述: 算式3*1!-4*2!+5*3!-6*4!+7*5!-8*6!+9*7!的值为()要有步骤 1个回答 分类:数学 2014-11-04 问题解答: 我来补答 =(2+1)*1! -(3+1)*2! +(4+1)*3! -(5+1)*4! +(6+1)*5! -(7+1)*6! +(8+1) *7!= (2! +1!) -(3!+2!) +(4!+3!) -(5!+4!) +(6!+5!) -(7!+6!) +(8!+7!)= 1 +8!= 40321 展开全文阅读