Question

Wn

求解這題🙏

a₁-6
+an-s
+a
n-4
+an-3 +an-2, +an+1+a₁₂ = 7
2d 3d 4d 5d "bd
9. 已知數列(an>為等差數列,且滿足9-+-+as-46+8=7
[a₁ + a₁₂+a₁₂+...+a₁ = 2044
n(+ (n-1)d)
,
則n =
2014 artd=1
(ai+hd-d)h=4088