In the arithmetic sequence {an}, A2 + A8 = 16, a3a7 = 48, find the general term formula of the sequence, and explain when D

A2 + A8 = A3 + A7 = 16, a3a7 = 48a3, a7 is about the two roots (X-12) (x-4) = 0x = 12 or x = 4 of the equation x ^ 2-16x + 48 = 0, that is, A3 = 12, a7 = 4 or A3 = 4, a7 = 12 when A3 = 12, a7 = 4, a7 = A3 + 4d4 = 12 + 4d4d = - 8D = - 2A3 = a1 + 2D12 = A1-2 * 2A1 = 16An = a1 + (n-1) d = 16-2 (n-1) = 18-2n when A3 = 4, a7

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