(1+1/11+1/13+1/17)(1/11+1/13+1/17+1/19)-(1+1/11+1/17+1/19)(1/11+1/13+1/17)求过程

分类: 作业答案 • 2022-06-28 11:15:43

问题描述：

(1+1/11+1/13+1/17)*(1/11+1/13+1/17+1/19)-(1+1/11+1/17+1/19)*(1/11+1/13+1/17)求过程

答

令a=1/11+1/13+1/17
原式=(1+a)(a+1/19)-(1+a+1/19)*a
=a²+(1+1/19)a+1/19-a²-a(1+1/19)
=1/19

(1+1/11+1/13+1/17)*(1/11+1/13+1/17+1/19)-(1+1/11+1/17+1/19)*(1/11+1/13+1/17)求过程