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已知等差数列{an}为递增数列,且a2,a5是方程x2-12x+27=0的两根,数列{bn...
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已知等差数列{a
n}为递增数列,且a
2,a
5是方程x
2-12x+27=0的两根,数列{b
n}的前n项和
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAEwAAAAjCAYAAAA+NeykAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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=
)
;
(1)求数列{a
n}和{b
n}的通项公式;
(2)若
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAEsAAAA4CAYAAAC1+AWFAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAxlJREFU
eF7tm4uRhCAMQLmWbeQKsBPrsAqb4AiCGxWXEKJGD2dubncGI3nmR2B/rLtMu2gEAFa7aAQMbVgb
5T2wYaATaLDorJplFbB6GqzR9sZY0w12svhzicr8sc9yw2my09jbbhjt0PV2nAbbGfefr3/Rnc+C
5VQbe2M7B2qY/Bdr+qtQPS4bgut1th+B1AzuQlZKYxZYDMQm+MM0sCVlXTDENAfXW6HApdANnZIL
oFnh+HVlSRHoN9MCoD4ZyFz6YEEQR7rVuNo0dC4ZSKFSHrNAWVIAR2679lrngkN06fqsqc+yvFVN
rjRIxKykN6GxqxgXYlagV2Oh8bFKYYXp+SDuSoWcK6Usa1NWgJXWZk7dsMDGqK64sbqxx1kQrK8+
K6qHxSs8nQviLCiUFZXDYlqEXxLFLDgXsjlPphQX6mB5t4sFKVtJHPTrs+AzAjzldV84Rp1lna87
v83z/2BVtHn+H6yKNo8IrE9ADlX3EqDT3893tW9P4Ld5EKz1sqG22r0XyJenF7V51nJmWGFZEQFJ
LA20wipu8yBFHKzZomos6VluyH+Nxi8nBBtk/Knov9NwF6r6VZOf4c6yGrxjyEvMinEn2zsSfGGl
se7O8aC2SJ0lyE+1qAar4PUQYMX9t9DqCC3cK921QJ9ThxJgwfND5zFWvxdvm59KoEA4DZbvPA7L
5qc/byDReiyYqIahJFgAxyynVZitXg3aVs6BAGvTwxZq/lfO+5bb87A2cKS3xGet0SGOMXPm6mD3
uUgGE3UW1hbO7JKCMct3POLuS2gTHa7qD3afi2QwSd1flO47HtnksbMshgwmr6xlMeXSbtuVIIzk
ISGDNtt7lzvbwxp+EV/YLpKQQWSlB1bcXC2t3zAsrowUrFQ4uN8Nw+YGQGIlDxTDymU4t3cnn7fX
EfR7YVHt/7RxaVjwuFSJpBgWf+f4wzYn4y2wKnaOF1hJGb/uONLB/iaq7x5mWTI/EPj+I4O3WJZf
AtX+QCAn4y2wKnaOFzfMyngJrJqd4wiLKwMfqMN1n+JseFq9wBbcYBWga7AKYP0B1ul9EUrprKIA
AAAASUVORK5CYII=
)
,s
n为数列{c
n}的前n项和,证明:s
n<1
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