解题方法
1 . 在某项投资过程中,本金为
,进行了
次投资后,资金为
,每次投资的比例均为x(投入资金与该次投入前资金比值),投资利润率为r(所得利润与当次投入资金的比值,盈利为正,亏损为负)的概率为P,在实际问题中会有多种盈利可能(设有n种可能),记利润率为
的概率为
(其中
),其中
,由大数定律可知,当N足够大时,利润率是
的次数为
.
(1)假设第1次投资后的利润率为
,投资后的资金记为
,求
与
的关系式;
(2)当N足够大时,证明:
(其中
);
(3)将该理论运用到非赢即输的游戏中,记赢了的概率为
,其利润率为
;输了的概率为
,其利润率为
,求
最大时x的值(用含有
的代数式表达,其中
).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c41d793c851a2f72f787913ba23e459c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a22baa009d2d45f6a37332ec3363285.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/903d7f7559c216e2516b9886c8f96008.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e60c0d3a709196db0791a93ed0db409.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf99487d7860d017c0747ff966edfd77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cad52924df9291d5d191d18e09374ee1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cdff4a44b674e8060072b7326549bf0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e60c0d3a709196db0791a93ed0db409.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdbd2aa0b04224ad335d43a53d81ae16.png)
(1)假设第1次投资后的利润率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2858005b9ae89ae080d83dcc13cf8e81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c41d793c851a2f72f787913ba23e459c.png)
(2)当N足够大时,证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f58c4f5f1d988a104655727aa501683c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd8f40e552f049c19252845917375c17.png)
(3)将该理论运用到非赢即输的游戏中,记赢了的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2858005b9ae89ae080d83dcc13cf8e81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b3e95410f3b4fcb0cba425b521d1f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5092000864ee720978d6d701c953a388.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c5439464042af3cbd35cf65be156.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85a89183e464e81e2c692ed239023ecd.png)
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2 . 已知数列
的前n项和为
,且满足
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/234605545a58197b26d52799abbb17b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06fbdd2e3efbef1ff014df55b242eced.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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2024-06-13更新
|
391次组卷
|
2卷引用:河北省张家口市2024届高三下学期第三次模拟考试数学试卷
3 . 已知数列
为等比数列,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/986c2bf3fd33b9af7dda6e83532581e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a4da25511377777245ca2ffa2efd768.png)
A.28 | B.32 | C.36 | D.40 |
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4 . 已知常数
,在成功的概率为
的伯努利试验中,记
为首次成功时所需的试验次数,
的取值为所有正整数,此时称离散型随机变量
的概率分布为几何分布.
(1)对于正整数
,求
,并根据
,求
;
(2)对于几何分布的拓展问题,在成功的概率为
的伯努利试验中,记首次出现连续两次成功时所需的试验次数的期望为
,现提供一种求
的方式:先进行第一次试验,若第一次试验失败,因为出现试验失败对出现连续两次成功毫无帮助,可以认为后续期望仍是
,即总的试验次数为
;若第一次试验成功,则进行第二次试验,当第二次试验成功时,试验停止,此时试验次数为2,若第二次试验失败,相当于重新试验,此时总的试验次数为
.
(i)求
;
(ii)记首次出现连续
次成功时所需的试验次数的期望为
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5eaba847ce18eb7fb4a9b2e12f6099c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(1)对于正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef133b0fd53a48310a82c18729575abd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13d9063d13b42af1249e6f83208482cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf3baba074e8aeb6f3ea117865bbd1b.png)
(2)对于几何分布的拓展问题,在成功的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4f150ab98bde511e0f65d9bafab031.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4f150ab98bde511e0f65d9bafab031.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4f150ab98bde511e0f65d9bafab031.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e599def7fc8d58e1f4f70e3f94e1cb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0f0ab88512620afb30d306754460263.png)
(i)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4f150ab98bde511e0f65d9bafab031.png)
(ii)记首次出现连续
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a78b3c84e7818ed70018eea40c72665.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a78b3c84e7818ed70018eea40c72665.png)
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解题方法
5 . 已知数列
是有无穷项的等差数列,
,公差
,若满足条件:①
是数列
的项;②对任意的正整数![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
,都存在正整数
,使得
.则满足这样的数列的个数是______ 种.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3068733ef2ceda9f1620d5c9bcdfa542.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ce64685821c3e55c07f151996ca8c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26a49a952a95f7af7d8b4bc55f0fbe03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14b6ff283e5a6152e31ebb40a1567710.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31118399bffb42470cdd4b3538970fe3.png)
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6 . 已知等比数列
的前
项和为
,则数列
的公比
满足( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fe87db12648c9af14827f3d06ce96b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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2024-04-02更新
|
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|
2卷引用:河北省张家口市2024届高三一模数学试题
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解题方法
7 . 已知数列
满足
,且
.
(1)求数列
的通项公式;
(2)设数列
的前
项和
满足
,对任意正整数
,试比较
与
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6065aaa8f3f103d1bc960da8318ce35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f69ead55a11bbc797d1743ecb3928360.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb47150cfafaa05a3d505467f7dc9518.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/686ece75006ad358f23314dc8a246e11.png)
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8 . 已知数列
是公比大于
的等比数列,下面叙述正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
A.当![]() ![]() | B.当![]() ![]() |
C.当![]() ![]() | D.当![]() ![]() |
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9 . 已知数列
满足
,
.
(1)若
,证明:数列
为等比数列;
(2)求数列
的前2n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbe7bdaaf8b0adf10bf2ef6c1255b1dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7511d52bc6cd793b7d4a1e9155d17cfa.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba33c874edc2b64d750866b80a5b0b82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b9a0d7150fb24be3e28ef7f0e18be93.png)
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解题方法
10 . 已知数列
是公比为q的等比数列,数列
是公差为d的等差数列,且
,
,则下列选项正确的有( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebaf2a2590bb84d646957f913d78f6dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b71c6e56da5da4a3cc0b2da1cf9dbbe9.png)
A.若![]() ![]() | B.若![]() ![]() |
C.若![]() ![]() | D.若![]() ![]() |
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