等差数列等比数列前n项和以及前n乘积的公式
展开全部
an=a1q^(n-1)
Sn = a1+a2+...+an
= a1(q^n-1)/(q-1)
Tn = a1.a2.a3.....an
= (a1)^n ( q.q^2...q^(n-1) )
=(a1)^n . q^[n(n-1)/2]
bn = b1+(n-1)d
Sn =b1+b2+...+bn = (2b1+(n-1)d)n/2
Tn = b1.b2....bn
= b1(b1+d)(b1+2d)...(b1+(n-1)d)
Sn = a1+a2+...+an
= a1(q^n-1)/(q-1)
Tn = a1.a2.a3.....an
= (a1)^n ( q.q^2...q^(n-1) )
=(a1)^n . q^[n(n-1)/2]
bn = b1+(n-1)d
Sn =b1+b2+...+bn = (2b1+(n-1)d)n/2
Tn = b1.b2....bn
= b1(b1+d)(b1+2d)...(b1+(n-1)d)
已赞过
已踩过<
评论
收起
你对这个回答的评价是？
推荐律师服务：
若未解决您的问题，请您详细描述您的问题，通过百度律临进行免费专业咨询
