(1+1×1⼀3)×(1+2×1⼀4)×(1+3×1⼀5)×(1+4×1⼀6)......(1+a×1⼀11)=?

2024-12-25 03:11:05
推荐回答(5个)
回答1:

依次类推,不管是乘到第几项,只要用第一项的分子4除以最后一项的分母n,在乘以(总的项数-1)个2,就可以得到结果

回答2:

(1+1×1/3)×(1+2×1/4)×(1+3×1/5)×(1+4×1/6)......(1+a×1/11)
=(3/3+1×1/3)×(4/4+2×1/4)×(5/5+3×1/5)×(6/6+4×1/6)......(1+9×1/11)
=[(3+1)/3]×[(4+2)/4]×[(5+3)/5]×[(6+4)/6]×.....×[(11+9)/11]
=4/3×6/4×8/5×10/6×.....×20/11
后一项的分子是前一项分母的2倍( 相约后等于2,一共有11-4+1=8 对可以约)
=4/11*2^8
=1024/11

回答3:

(1+1×1/3)×(1+2×1/4)×(1+3×1/5)×(1+4×1/6)......(1+9×1/11)
=5/3*6/4*8/5*10/6*.........*20/11
=1280/11

回答4:

(1+1/3)(1+2/4),,
提取公因式(1+(x-2)/x)=(2(x-1)/x)!=2*((x-1)/x)!
原式等于(1+(x-2)/x)! (x=11), ,即2*10/11的阶乘

回答5:

(1+1×1/3)×(1+2×1/4)×(1+3×1/5)×(1+4×1/6)×.....×.(1+9×1/11)
=4/3×6/4×8/5×10/6×……×20/11
=4×6/3×8/4×10/5×……×20/10×1/11
=4×2^8×1/11
=1024/11