1、設(shè){an}是各項(xiàng)均為正數(shù)的等比數(shù)列,前4項(xiàng)之和等于其前2項(xiàng)和的10倍,則該數(shù)列的公比為______.
2.設(shè){an}是由正數(shù)組成的等比數(shù)列,且a5a6=81,log3a1+ log3a2+…+ log3a10的值是______
3、已知數(shù)列{an}是公比q≠1的等比數(shù)列,則在 “(1){anan+1}, (2){an+1-an}, (3){an3},(4){nan}”這四個(gè)數(shù)列中,成等比數(shù)列的個(gè)數(shù)是______
4.在等比數(shù)列an中,前三項(xiàng)分別為1,q,q,第二項(xiàng)加上2后構(gòu)成等差數(shù)列, 2則q=______
5、設(shè)α、β是方程x2-2x+k2=0的兩根,且α,α+β,β成等比數(shù)列,則______
2.設(shè){an}是由正數(shù)組成的等比數(shù)列,且a5a6=81,log3a1+ log3a2+…+ log3a10的值是______
3、已知數(shù)列{an}是公比q≠1的等比數(shù)列,則在 “(1){anan+1}, (2){an+1-an}, (3){an3},(4){nan}”這四個(gè)數(shù)列中,成等比數(shù)列的個(gè)數(shù)是______
4.在等比數(shù)列an中,前三項(xiàng)分別為1,q,q,第二項(xiàng)加上2后構(gòu)成等差數(shù)列, 2則q=______
5、設(shè)α、β是方程x2-2x+k2=0的兩根,且α,α+β,β成等比數(shù)列,則______