Contact us
Choose a category below so we can get back to you as quickly as possible.
建議你去看看百科“等比數列”! 假設你題目對的話,那麼從第二項開始,是等比為a,初始項為a^2的等比數列! 則第二項開始的和為:(a^2-a^(n-1)*a)/(1-a)=(a^2-a^n)/(1-a) 囙此所求Sn=1+和=1+(a^2-a^n)/(1-a),n≥3,s1=1,s2=1+a^2
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.