設{An}是由正數組成的等比數列,公比q=2,且A2A2A3......A30=2^30,則A3A6A9......A30等于多少?設{An}是由正數組成的等比數列,公比q=2,且A2A2A3......A30=2^30,則A3A6A9......A30等于多少?

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A1A3=A2^2,A4A6=A5^2.......A28A30=A29^2(A2A5A8......A29)^3=2^30A2A5A8......A29=2^10A3A6A9......A30=(A2A5A8......A29)*q^10=2^10*2^10=2^20