(1+19/92)+(1+19/92 ×2)+(1+19/92 ×3)+…+(1+19/92 ×14)+(1+19/92 ×15)
来源:百度知道 编辑:UC知道 时间:2024/06/17 18:14:25
用简便运算哦!先谢谢了!
(1+19/92)+(1+19/92 ×2)+(1+19/92 ×3)+…+(1+19/92 ×14)+(1+19/92 ×15)=15+(1+2+3+...+15)*19/92=15+120*19/92
原式=1*15+(19/92)*(1+2+…+15)
=15+(19/92)*[(1+15)*15/2]
=15+(19/92)*120
=3660/92
=915/23
不知道算不算简便,我就只把19/92的系数先提取出来相加
(1+19/92)+(1+19/92 ×2)+(1+19/92 ×3)+…+(1+19/92 ×14)+(1+19/92 ×15)
(1+19/92)+(1+19/92 ×2)+(1+19/92 ×3)+…+(1+19/92 ×10)+(1+19/92 ×11)
1/(12×13)+1/(13×14)+1/(14×15)。。。+1/(19×20)=?
1/(16*17)+1/(17*18)+1/(18*19)+1/(19*20)怎么算最简便
(1+1/11+1/13+1/17)×(1/11+1/13+1/17+1/19)-(1+1/11+1/13+1/17+1/19)×(1/11+1/13+1/17)
1/(12×13)+1/(13×14)+……+1/(19×20)=???
公务员题1/(12*13)+1/(13*14)+1/(14*15)+.......+1/(19*20)
我是金牛的,(19/5)她是水瓶的,(27/1)配吗?
1/(12×13)+1/(13×14)+……+1/(19×20)的值为多少?是如何计算的?
1/1*3+1/3*5+1/5*7+......+1/17*19+1/19*21