(文)(1)依题设A1(?a,0),A2(a,0),则FA,0),FA2?(a?1,0). 1?(?a?1由FA1?FA2??1,解得a?2,所以b?1.
22x2所以椭圆C的方程为?y2?1.
2(2)依题直线l的方程为y?k(x?1).
由??y?k(x?1),22222k?1x?4kx?2k?2?0. 得??22?x?2y?2设A(x1,y1),B(x2,y2),弦AB的中点为M(x0,y0),
?k4k22(k2?1)2k2y?xx?则x1?x2?,,,, x?01202k2?12k2?12k2?12k2?12k2?k所以M(2,2).
2k?12k?112k2??(x?2), 直线MD的方程为y?2k2?1k2k?1kk2k2,0). 令y?0,得xD?,则D(222k?12k?1若四边形ADBE为菱形,则xE?xD?2x0,yE?yD?2y0.
3k2?2k,2). 所以E(22k?12k?13k22?2k)?2(2)2?2. 若点E在椭圆C上,则(22k?12k?12整理得k?2,解得k?42.所以椭圆C上存在点E使得四边形ADBE为菱形.
xxxx22.理(1)3?(2?3?8)?9?9,3?9,x?2
(2)p(10071311007131)?q()??. )?p()??,q(201426220142232 11
因为p(x)?p(1?x)?3x3?3x?31?x31?x?3?3x3?3x?33?3x?1,
9x91?x9x3q(x)?q(1?x)?x?1?x?x?x?1
9?39?39?39?3所以,p(1220131)?p()???p()?1006?, 20142014201421220131q()?q()???q()?1006?. 2014201420142122013122013p()?p()???p()=q()?q()???q(). 201420142014201420142014(3)因为f(x)??(x?1)?a是实数集上的奇函数,所以a??3,b?1.
?(x)?bf(x)?3(1?2),f(x)在实数集上单调递增. x3?1由f(h(x)?1)?f(2?k?g(x))?0得f(h(x)?1)??f(2?k?g(x)),又因为f(x)是实数集上的奇函数,所以,f(h(x)?1)?f(k?g(x)?2),
又因为f(x)在实数集上单调递增,所以h(x)?1?k?g(x)?2 即32x?1?k?3x?2对任意的x?R都成立,
x即k?3?1对任意的x?R都成立,k?2. x3(文)(1)an?2?6(n?1)?6n?4 (2) a1?2,a2?8,a3?6,
a4??2,a5??8,a6??6,a7?2,a8?8,a9?6,a10??2,a11??8, a12??6,我们发现数列为一周期为6的数列.事实上,由an?1?an?1?an有
an?3?an?2?an?1??an,an?6?an?3?3??an?3?an.??8分(理由和结论各2分)
因为 2014?335?6?4,所以a2014?a4??2.
(3)假设存在常数c,使an?3?an恒成立.
由an?1?an?1?can ○1,
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及an?3?an,有an?2?an?can?1?an?1?an?can?1 ○2 1式减○2式得(an?1?an)(1?c)?0. ○
所以an?1?an?0,或1?c?0.
当n?N*,an?1?an?0时,数列{an}为常数数列,不满足要求.
由1?c?0得c??1,于是an?1?an?1??an,即对于n?N且n?2,都有
an?1??an?an?1,所以 an?3??an?2?an?1,an?2??an?1?an,从而
an?3??an?2?an?1,?an?1?an?an?1?an (n?1).
所以存在常数c??1,使an?3?an恒成立. 23.理(1)b1?aa1?a1?1,
bn?aan?a2n?1?22n?1?14n?1?;
2(2)根据反证法排除a1?1和a1?3(a1?N*)
证明:假设a1?2,又an?N*,所以a1?1或a1?3(a1?N*) ①当a1?1时,b1?aa1?a1?1与b1?3矛盾,所以a1?1;
②当a1?3(a1?N*)时,即a1?3?b1?aa1,即a1?aa1,又an?an?1,所以a1?1与
a1?3(a1?N*)矛盾;
由①②可知a1?2.
(3)首先?an?是公差为1的等差数列, 证明如下:
an?1?an?n?2,n?N*时an?an?1,
所以an?an?1?1?an?am?(n?m),(m?n,m、n?N)
*?aan?1?1?aan?1?[an?1?1?(an?1)]即cn?1?cn?an?1?an
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由题设1?an?1?an又an?1?an?1?an?1?an?1 即?an?是等差数列.又?an?的首项a1?1,所以an?n,
Sn??(2?2?22?3?23???n?2n),对此式两边乘以2,得 2Sn??22?2?23?3?24???n?2n?1
两式相减得Sn?2?22?23???2n?n?2n?1?2n?1?n?2n?1?2
Sn?n?2n?1?2n?1?2,Sn?n?2n?1?50即2n?1?52,当n?5时,2n?1?64?52,
即存在最小正整数5使得Sn?n?2n?1?50成立. 注:也可以归纳猜想后用数学归纳法证明an?n.
xxx(文)(1)h(x)?8g(x)?h(1)?0即:9?8?3?9?0,解得3?9,x?2
(2)p(1007131)?p()??. 201422323x3?3x因为p(x)?p(1?x)?所以,p(?31?x31?x?3?3x3?3x?33?3x?1,
12201312013)?p()???p()?1006??, 20142014201422(3)同理科22(3).
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