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In the equal ratio sequence {an}, A6 = 6, A9 + 9, then A3 is equal to?
There is A6 * A6 = A3 * A9! So A3 = 4!
In the equal ratio sequence {an}, if A6 = 6, A9 = 9, then A3 is ()
A. 4B. 32C. 169D. 2
∵ A3 = a1q2, A6 = a1q5, A9 = a1q8, ∵ a3a9 = (A6) 2, A3 = a62a9 = 629 = 4
In the equal ratio sequence an, A3 = - 54, A6 = 54, then A9=
In the equal ratio sequence, (A6) &# 178; = (A3) × (A9)
Result: A9 = - 54
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