若数列{an},{bn}都是等差数列,s,t 为已知常数,求证数列{ s an+t bn}是等差数列
若数列{an},{bn}都是等差数列,s,t 为已知常数,求证数列{ s an+t bn}是等差数列
已知数列{an}是等差数列,且bn=an+a(n-1),求证bn也是等差数列
已知数列an是等差数列,且bn=an+a(n+1).求证数列bn是等差数列.
已知数列{An}是等差数列,且Bn=An+A(n+1).求证数列{Bn}是等差数列
已知数列{an}得前n项和为sn=an^2+bn(a,b为常数且a不等于0)求证数列{an}是等差数列
已知{an}是等差数列,bn=kan+m(k,m为常数).求证{bn}是等差数列
已知数列{an}是等差数列,且bn=3an+1 1.求证:数列{bn}是等差数列 2.若a1=2,
已知数列{an}是等差数列,且bn=2的an次方,求证数列{bn}是等比数列
已知数列an是等差数列 且bn=2^a{n}求证bn为等比数列 {}里为下标 ^为上标
已知数列{an}、{bn}是等差数列.求证:{pan+qbn}是等差数列.
已知数列{bn}是等差数列,a>0,求证数列{an的b次方}是等比数列
已知数列{An}及数列{Bn}都为等差数列,Cn=An+Bn,证数列{Cn}为等差数列