等差数列AN,公差D不等于0,A1,A2,A3,A4等比数列,则(A1+A5+A17)/(A2+A6+A18)=?

是A1,A3,A4等比数列吧?∵A1,A3,A4等比数列∴(a3)²=(a1)×(a4)(a1＋2d)²=(a1)(a1＋3d)a²₁+4d²+4a1d=a²₁+3a1d4a1d＋4d²=3a1da1d＋4d²=0d(a1+4d)=0∵d≠0∴a1+d=0 即a1=-4d(A1+A5+A17)/(A2+A6+A18)=(A1+A1+4d+A1+16d)/(A1+d+A1+5d+A1+17d)=(3A1+20d)/(3A1+23d)=(-12d+20d)/(-12d+23d)=8f/11d=8/11