设等比数列an的公比q=2,前n项和为sn,则s4除以a2=
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/06 23:52:36
![设等比数列an的公比q=2,前n项和为sn,则s4除以a2=](/uploads/image/z/5605911-63-1.jpg?t=%E8%AE%BE%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97an%E7%9A%84%E5%85%AC%E6%AF%94q%3D2%2C%E5%89%8Dn%E9%A1%B9%E5%92%8C%E4%B8%BAsn%2C%E5%88%99s4%E9%99%A4%E4%BB%A5a2%3D)
x){nOy6uӎyg<]CMDC-#b} *od_\gr
设等比数列an的公比q=2,前n项和为sn,则s4除以a2=
设等比数列an的公比q=2,前n项和为sn,则s4除以a2=
设等比数列an的公比q=2,前n项和为sn,则s4除以a2=
S4=a1(1-2^n)/(1-2)=a1(2^n-1)
a2=a1*2
S4/a2=(2^n-1)/2