1)a+b=a(n+1)/an,ab=1/an
6a-2ab+6b=[6a(n+1)-2]/an=3
a(n+1)=(3an+2)/6
2)求证:数列{an-1/3}是等比数列
a(n+1)-1/2=(3an+2)/6-1/3=an/2
a(n+1)/an=1/2
是等比数列
2)a(n+1)=(3an+2)/6
1)a+b=a(n+1)/an,ab=1/an
6a-2ab+6b=[6a(n+1)-2]/an=3
a(n+1)=(3an+2)/6
2)求证:数列{an-1/3}是等比数列
a(n+1)-1/2=(3an+2)/6-1/3=an/2
a(n+1)/an=1/2
是等比数列
2)a(n+1)=(3an+2)/6