作业帮求和Sn=(x-1)+(x^3-2)+(x^5-3)+(x^7-4)+…+(x^2n-1-n)
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/28 00:21:51
x){餞<[
]CMm8c]#0mk uM4 5,t
u4mԩ_`gC豭*bSm===m1XPP$bhiAd+4
5u+b@(/.H̳z:!@ 4@6 9|k
求和Sn=(x-1)+(x^3-2)+(x^5-3)+(x^7-4)+…+(x^2n-1-n)
求和Sn=(x-1)+(x^3-2)+(x^5-3)+(x^7-4)+…+(x^2n-1-n)
求和Sn=(x-1)+(x^3-2)+(x^5-3)+(x^7-4)+…+(x^2n-1-n)
Sn=(x-1)+(x^3-2)+(x^5-3)+(x^7-4)+…+(x^2n-1-n)
=x+x^3+x^5+...+x^2n-1 -(1+2+3+...+n)
=x(1-x^2n)/(1-x)-(1+n)n/2
=[x^(2n+1)-x]/(x-1)-(1+n)n/2
Sn=x+x^3+x^5+...+x^2n-1 -(1+2+3+...+n)
=x(x^2n-1)/(x^2-1)+n(n+1)/2