急死人了啊!!!求解~~

来源:百度知道 编辑:UC知道 时间:2024/06/11 23:36:29
(1+1/2)(1+1/2^2)(1+1/2^3)(1+1/2^4)(1+1/2^5)(1+1/2^6)(1+1/2^7)(1+1/2^8)(1+1/2^9)(1+1/2^10)=??????这道题的答案到底是多少啊!!!14点30之前要答案!!!详细的解答过程啊!
2种都不行啊!!!第二种看上去行,其实不行~~

在最左边乘以(1-1/2),则变成了(1-1/2)(1+1/2)(1+1/2^2)(1+1/2^3)(1+1/2^4)(1+1/2^5)(1+1/2^6)(1+1/2^7)(1+1/2^8)(1+1/2^9)(1+1/2^10)=(1-1/2^2)((1+1/2^2)(1+1/2^3)(1+1/2^4)(1+1/2^5)(1+1/2^6)(1+1/2^7)(1+1/2^8)(1+1/2^9)(1+1/2^10)=...=1-1/2^11=2047/2048,最后,再除以(1-1/2),得2047/1024

1- 1/2*2 )(1- 1/3*3 )......(1- 1/100*100)
=(1+1/2)(1-1/2)(1-1/3)(1+1/3)…………(1-1/100)(1+1/100)
=[(1-1/2(1-1/3)……(1-1/100)][(1+1/2)(1+1/3)……(1+1/100)]
=[(1/2)*(2/3)*(3/4)*……(99/100)][(3/2)*(4/3)*(5/4)……(101/100)]
=1/100*(101/2)
=101/200