Contact us
Choose a category below so we can get back to you as quickly as possible.
因為2Sn=3an-1 所以2Sn+1= 3an+1 - 1 下麵的减上面的得 2an+1=3an+1 - 3an-1 所以an+1=3an-1 所以等比數列公比3 2Sn=3an-1代入N=1 得a1=1所以an=3^n-1
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.