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2023高一数学月考卷

 昵称20643483 2023-08-31 发布于江西

高一上学期月考数学试题

考试时间:120分钟;满分150分。

第I卷(选择题)

一、单选题:本题共8小题,每小题5分,共40分.在每小题给出的四个选项中,只有一项是符合题目要求的.

1.设集合eqId7a7f8a8c2a8dc3d318780df39a7d89aceqId50f0117571b278a845d7e9ab07764b6e,则eqIdb4b9b470218359a4a47be9244980489e    

AeqIdde6da5105b9ca302dd85336ed3c914a4                    BeqId0cdc0ce1e00da623ca4d3572085ff5ee

CeqIda946a8724cedd72c0905661a34ee3ace                        DeqIda1bdcc4038697529f45196bebe1a4cf2

2.命题eqId1c780149aef1bd77162e85f7f8906a6aeqIdf3a29ff368565ed52f3741a156444a33的否定为(    

AeqId1c780149aef1bd77162e85f7f8906a6aeqId7186be40754bf66a1e932c786f59920e        BeqId1c780149aef1bd77162e85f7f8906a6aeqId0d312b50def1f5ca3822dec6860b9d5a

CeqId1485a4756c56f1126b9825d5019d544ceqIdf3a29ff368565ed52f3741a156444a33         DeqId1485a4756c56f1126b9825d5019d544ceqId7186be40754bf66a1e932c786f59920e

3.设eqIdc4166972dec0aa3e8694a44eeb941a08,则eqId8ef99608dd5bee4bfb83494af9912f4eeqId99d7066ade8f8dd37fe180739e073f5f的(    

A.充分不必要条件                B.必要不充分条件

C.充要条件                      D.既不充分也不必要条件

4.满足条件eqId4f461fe518e530091f8e34e4968e81fd的所有集合eqIdac047e91852b91af639feec23a9598b2的个数是(    

A4      B8       C16       D32

5.已知实数eqId0a6936d370d6a238a608ca56f87198deeqId2c94bb12cee76221e13f9ef955b0aab1eqId071a7e733d466949ac935b4b8ee8d183,且eqId432d77fe5ad3032d59a237dd94c8a638,则下列不等式正确的是eqIdfd995178601c2ad7b40f973d268c7bb7     eqId04582116cd765fcc5a52f44279ad6c94

AeqId26f7c54faca6eac8af5309942062058d   BeqId0cb54b1b3617ebc502cb44194cbcd1dc      CeqId3146bea1f50ef01e8c71a090b8f0e2a8     DeqId3c22b9d08cf536bbb76bce1b0f135772

6.已知eqId752455799e49f846e2601304fec5d3b8,且eqIdd623f8e132aa851def9ed6d705494fc7的最小值为(    

A10       B9         C8          D7

7.某公司购买一批机器投入生产,若每台机器生产的产品可获得的总利润s(万元)与机器运转时间t(年数,eqIdd717b62cf19a284dacacfb596fc1d9dc)的关系为eqId33986c51ec1146cd3a2af0b566a3f7bf,要使年平均利润最大,则每台机器运转的年数t为(    

A5                           B6                           C7                           D8

8.下列命题中,正确的是(    

A.若ab0,则a2abb2                       B.若ab0,则eqIdec71b0c4b7547abc181ee21592aab32a

C.若ba0c0,则eqId90882db1028f1e2440339d203c1901e6                     D.若abR,则a4b4≥2a2b2

二、多选题:本题共4小题,每小题5分,共20分.在每小题给出的选项中,有多项符合题目要求,全部选对的得5分,部分选对的得2分,有选错的得0分.

9.下列选项中的两个集合相等的是(    ).

AeqId3d2b3767542016e1aca66feb369c266ceqId0ad0d3498c722740bb3a52e69b9b54ca

BeqId7a41a18c8d86d7dcbf7b83a01ac8617eeqId980facf3752a3d4e86b60d653c5c4aa7

CeqId76abb6aca050ddfde1136acfcdaa74eaeqId7bdea20233425b4482ef6aa283c9fd2c

DeqIdaefbe3fc1cf1ea821292d6e5dada671feqId751a4681d6d55295d4d31fa5ca19fc8f

10.给出下列四个条件:其中能成为eqId2b21208364124b5c477b2ff8df1c2e8f的充分条件的是(    

AeqId37a96d5fe8e2a8404e53ac181f66aad6     BeqId04ece3ec7e18481e0ba5d3054edac5bc     CeqId7d33fd931000188eab07530018fcb61e      DeqIdba8073266cfa99b04190473d16b615a8

11.已知关于eqId81dea63b8ce3e51adf66cf7b9982a248的不等式eqIdf95f3fa710253c107b6e8fb458108b0d的解集为eqId8d499401d9f11b3caf916d74918810c3eqId074a2025262fb224ccab1efd1c8c992b,则下列结论中,正确结论的序号是(    

AeqId94440d3e4c073f94f2b266ff99d50e74             B.不等式eqId42afcaa5895d8f16e8280d004cec4da2的解集为eqIda85e60d556c0a7f4b7e023c0fa459bff

C.不等式eqId009db35e84f9e2ed847519211918fbfe的解集为eqId342e29e09b521edf70b5e9680e7b502ceqIdb14899226f631592c180e64b65870c6f  DeqId12e7ef804eeb23618fbf91ead47587f2

12.下列结论错误的是(    

A.不存在实数a使得关于x的不等式eqIdd1611384d4189225cbaf70c0f9fa3205的解集为eqId9a837165ca03f9e4ea8964979c95e3bb

B.不等式eqId9aa504a3525899b292b2b53aae50fcbeR上恒成立的必要条件是eqId9e10e1c43b86a8cd4360ca9b57232164eqIda4fb3aeb60930ed6d1e828d4306493a8

C.若函数eqId8352b2e643a7ce605334f1b0e572bfb0对应的方程没有实根,则不等式eqId5b5f28031b036e4a37be931d5ff28368的解集为R

D.不等式eqIdf180f35219346b1ebb54250511d03600的解集为eqId7ccaa6e503b61e9ae78d8439cba2e328

第II卷(非选择题)

三、填空题:本题共4小题,每小题5分,共20分.

13.若eqId2498d5578b17cadbf2c64e9eb763303b,则eqId81dea63b8ce3e51adf66cf7b9982a248的值为__________.

14.已知eqIddc1d80797a6ada33ee435a586ebd52f0,则函数eqId79469461f9ea7d95fcf9a949033f1a1c的最大值为____________

15.若0<a<1,则不等式(ax)eqId44b29470b3cdad553b4c3c3f8ff17b5e >0的解集是________

16.已知eqId08115d6d9f876dea921a4d32260ff1fbeqId061813f1ec633c5c4c393c4de7938322,且eqId04645353d91a5beb6d02c06bb62683a9,若eqIdecf0760b8fbbeb6f2a90607348fd78a2恒成立,则实数eqId294f5ba74cdf695fc9a8a8e52f421328的取值范围是_______

四、解答题:17题10分,18-22每题12分,共70分.解答应写出文字说明、证明过程或演算步骤.

17.已知集合eqId156467b49aeb3588c90a88df5b1a828e,集合eqId5041bc91dc7835b2f9cb15bd950d4dd8

(1)eqId8fdbfa7a63fdf5717d40c8c9a73ec160

(2).

18.已知集合eqIde77c293ec47e9efcd10ad5060fb59d6a,集合eqId623e00621610db2afc3466011c9e1175

(1)eqIdeaf140ea69179c08a3a4951d346deb84,求eqIdb3744e71abf4b43e128eabea9181b712

(2)eqId0b05d2be27e8f53e4de3071846dffb41,求实数eqId0a6936d370d6a238a608ca56f87198de的取值范围.

19.已知不等式eqId1f670cbb654f0f1dc28d0203d10d8fcd

1)若不等式的解集为eqIdf20c78ad990e2424f4ece6a926e17baeeqIde8d5c65d76b90bafe1a009ef1693af2f,求实数eqId0a6936d370d6a238a608ca56f87198de的值;

2)若eqId03837b3769eda7f0d3804cc5ad4a6d60,解该不等式.

20.已知集合eqId7c27c6d191ae40039121e2a63d43bfe2,命题p不等式eqId4b6d03dfc5b4ce38e17403b3b49fdc15对一切实数x都成立.

(1)若命题p是真命题,求实数k的取值范围;

(2)当命题p是真命题时,记实数k的取值范围对应集合为集合B,若eqIddd9d50619b779c1056602f46b2a95e90,求实数m的取值范围.

21.已知正实数eqIdd708cb763716467219215cdc0782c0a6满足eqId77633474efcd1a2f69a8c5e485b18ec2

(1)eqIdb55e279e837b94cda37321e987861401的最小值;

(2)eqIdabcffb3ef863243947ccf13337a1492b恒成立,求实数eqId0a6936d370d6a238a608ca56f87198de的取值范围.

22.设eqIda3c064ae009310ae784b79a775cbed31

(1)若不等式eqId1e59bb4bf2e0698d876cf815362b3658对一切实数eqId81dea63b8ce3e51adf66cf7b9982a248恒成立,求实数eqId294f5ba74cdf695fc9a8a8e52f421328的取值范围;

(2)在(1)的条件下,求eqIdb9aaa48c24bcd35f215d27adcb5d00f1的最小值;

(3)解关于eqId81dea63b8ce3e51adf66cf7b9982a248的不等式eqId0c6bd18f506732ba8f2163736ecec9d7

参考答案:

1C

【分析】直接进行交集运算即可求解.

【详解】因为集合eqId7a7f8a8c2a8dc3d318780df39a7d89aceqId50f0117571b278a845d7e9ab07764b6e

eqIdd3a3c9285ba69e99ce48673660a2e576

故选:C.

2D

【分析】根据全称命题的否定的求解,改量词,否结论即可求得结果.

【详解】全称量词命题的否定是存在量词命题,

故原命题的否定是:eqId1485a4756c56f1126b9825d5019d544ceqId7186be40754bf66a1e932c786f59920e.

故选:D.

3B

【分析】分别求解一元二次不等式与一元一次不等式,然后结合充分必要条件的判定得答案.

【详解】eqId8ef99608dd5bee4bfb83494af9912f4e,解得eqId200849ce71f53c0321506e27de437b8deqId752455799e49f846e2601304fec5d3b8

eqId99d7066ade8f8dd37fe180739e073f5f,得eqId16688590aa75a979cc269d934f1bf899

即由eqId8ef99608dd5bee4bfb83494af9912f4e不能得到eqId99d7066ade8f8dd37fe180739e073f5f,反之,由eqId99d7066ade8f8dd37fe180739e073f5f,能够得到eqId8ef99608dd5bee4bfb83494af9912f4e

即“eqId8ef99608dd5bee4bfb83494af9912f4e是“eqId99d7066ade8f8dd37fe180739e073f5f的必要不充分条件.

故选:B

4B

【分析】根据集合并集的定义由所有属于集合A或属于集合B的元素所组成的集合叫做并集进行反向求解即可.

【详解】∵{135}∪M={13579}

∴7∈M,且9∈M

的集合M可能为{79}{179}{379}{579}{1379}{1579}{3579}{13579}

故选B

【点睛】本题考查了并集概念的灵活应用,属于基础题.

5C

【分析】利用特值可进行排除,由不等式性质可证明C正确.

【详解】若a1b=﹣1,则AB错误,若c0,则D错误,

ab

a+1abb1

a+1b1,故C正确,

故选C

【点睛】本题主要考查不等式与不等关系,在限定条件下,比较几个式子的大小,可用特殊值代入法,属于基础题.

6D

【分析】构造基本不等式求最小值.

【详解】因为eqId752455799e49f846e2601304fec5d3b8,所以eqId9ac299f84c6133a8470c5617761924c8

所以eqId2d55b672d71d4d12e27d57241cdca0fc,当且仅当eqIdcc822210c34340a98a3da05edc0cc81c,即eqIdda322ac8867e8a47c6588601078abf18时取等号.

故选:D.

7D

【分析】根据题意求出年平均利润函数。利用均值不等式求最值.

【详解】因为每台机器生产的产品可获得的总利润s(万元)与机器运转时间t(年数,eqIdd717b62cf19a284dacacfb596fc1d9dc)的关系为eqId33986c51ec1146cd3a2af0b566a3f7bf

所以年平均利润eqIdbb90d8e267e372760b2273691fd857d4

当且仅当eqIdd535a4d2666de49bb57c25c8808f0feb时等号成立,

即年平均利润最大,则每台机器运转的年数t8

故选:D

8D

【分析】利用不等式的性质可判断AC;利用基本不等式可判断B,利用作差法可判断D

【详解】解:对于AeqIdca24341509c05e672999202f2df0ebaf,则eqId0c2ca67148f90890830b769c6a92c0be,故A错误;

对于BeqId94ed37ee7432002cd0e0978b2012e184eqId05b07bd5bd1885d7a32e2c33e9619010异号,eqId71d2c4eab2e9dd152f995cfa1f87df7b当且仅当eqIdbec8f6a68e0710eb8da47d9f2039c640时等号;

对于C,由eqId2f05930837039d924f84f12ec886733deqId6711e06cd61ac21656512e33f4ee2cd6,又eqIdf75807858b7804a1ad2039c41f323a18,则eqId288420f0b137ec90d963e6b5db65fe30,故C错误;

对于D,由eqId9eea36570eda98973f53eb83069b882b,得eqId1d67549bbfe683f708b7c184aa8792b0,故D正确.

故选:D

9AC

【分析】首先判断两集合的元素特征,即可判断.

【详解】解:对于AeqId3d2b3767542016e1aca66feb369c266ceqId0ad0d3498c722740bb3a52e69b9b54ca,集合eqIddad2a36927223bd70f426ba06aea4b45eqIdacc290b44635265137fdf13146b6a6d9均为偶数集,故eqId7a263d5e89becaaa2474a711da1c2c2c,即A正确.

对于BeqId9ce5267b0d4b36159fb18f0e66c6c162

eqId99cd6d0f6da66c108ff02b000a58dfc2,故eqIdc62b61a723d1ab1907093bb82c3794d6,即B错误;

对于CeqId617acd9f6c811b71f3bb16791fe055b0,当eqIdb6a24198bd04c29321ae5dc5a28fe421为偶数时,eqId9172c6aeb26c99b70ac007a7e7b9963f

eqIdb6a24198bd04c29321ae5dc5a28fe421为奇数时,eqId686f61f32c07b8fdf63fa43ad7e0f308,即eqId3a3e4f486c9c5124c3ef60522ae021e2,所以eqId7a263d5e89becaaa2474a711da1c2c2c,故C正确;

对于DeqId606bb4773f495d2ab2396849343bfe6feqId751a4681d6d55295d4d31fa5ca19fc8f为点集,故eqIdc62b61a723d1ab1907093bb82c3794d6,即D错误;

故选:AC

10BC

【分析】由不等式的性质即可得出结论.

【详解】A中,若eqId6d2be44deec9d3c3eb6b456488b29358,则不能得到eqId2b21208364124b5c477b2ff8df1c2e8fA错误;

B中,若eqId04ece3ec7e18481e0ba5d3054edac5bc,则有eqId2b21208364124b5c477b2ff8df1c2e8f,满足充分性,B正确;

C中,若eqId7d33fd931000188eab07530018fcb61e,则有eqId6d229cbec798c9c278a9b5979cb38247,是eqId2b21208364124b5c477b2ff8df1c2e8f的充分条件,C正确;

D中,若eqIdba8073266cfa99b04190473d16b615a8,则eqId0f23be9638a5d5934d0a3c55f3156b81,不能得到eqId2b21208364124b5c477b2ff8df1c2e8fD错误.

故选:BC

11AD

【分析】由一元二次不等式的解集可确定eqId94440d3e4c073f94f2b266ff99d50e74,并知eqId13fa32c1e926f40a0722d106563777ef两根为eqId5ca7d1107389675d32b56ec097464c14eqIdb8860d9787671b53b1ab68b3d526f5ca,利用韦达定理可用eqId0a6936d370d6a238a608ca56f87198de表示eqIdc9a475fec8ded321e10a6697319fb975,由此将不等式中eqIdc9a475fec8ded321e10a6697319fb975eqId0a6936d370d6a238a608ca56f87198de替换后依次判断各个选项即可得到结果.

【详解】对于A,由不等式的解集可知:eqId94440d3e4c073f94f2b266ff99d50e74eqId25535f0dea11c9f94c547c14f7aebc5beqId9839c35d8c2bc3d96192ad3434ff7e02eqId13bc970cbf9701201dee91c15d4b92c1A正确;

对于BeqIddbb99efcdb61692e38baf0a73bab154d,又eqId94440d3e4c073f94f2b266ff99d50e74eqId85d0f816cdeb63f1796f9e99131bfa6bB错误;

对于CeqId2c221834508cca39dd73e88cfdcdadc4,即eqIdd1429405d025dba07505da3500d1c6e3,解得:eqId687a484d82252a5bb2aebf473a54555eC错误;

对于DeqId9981fa71effb8ad0c457a13dd3e0498fD正确.

故选:AD.

12CD

【分析】根据题意,结合一元二次不等式和分式不等式的解法,一一判断即可.

【详解】对于选项A,当eqIdce3a34d6f60032718820c3da2b07786b时,eqIdd1611384d4189225cbaf70c0f9fa3205的解集不为eqId9a837165ca03f9e4ea8964979c95e3bb,而当eqId9e10e1c43b86a8cd4360ca9b57232164时,要使不等式eqIdd1611384d4189225cbaf70c0f9fa3205的解集为eqId9a837165ca03f9e4ea8964979c95e3bb,只需eqIda6e18e65d7bb7c6f220eec04d03dcccd,即eqId2b70f8691af2a1d287aa5c476ede5e7e,因eqId9e10e1c43b86a8cd4360ca9b57232164,故不存在实数a使得关于x的不等式eqIdd1611384d4189225cbaf70c0f9fa3205的解集为eqId9a837165ca03f9e4ea8964979c95e3bb,因此A正确;

对于选项B,当eqId9e10e1c43b86a8cd4360ca9b57232164eqIda4fb3aeb60930ed6d1e828d4306493a8时,eqId9aa504a3525899b292b2b53aae50fcbeR上恒成立,故不等式eqId9aa504a3525899b292b2b53aae50fcbeR上恒成立的必要条件是eqId9e10e1c43b86a8cd4360ca9b57232164eqIda4fb3aeb60930ed6d1e828d4306493a8,因此B正确;

对于选项C,因函数eqId8352b2e643a7ce605334f1b0e572bfb0对应的方程没有实根,但eqId0a6936d370d6a238a608ca56f87198de正负不确定,故eqId5b5f28031b036e4a37be931d5ff28368eqIdf84617aaab200384efeaec9a4fe71772恒成立,因此不等式eqId5b5f28031b036e4a37be931d5ff28368的解集不一定为R,故C错;

对于选项D,由eqIdf180f35219346b1ebb54250511d03600,得eqId4e4ec8dccd929e7880cbd4a39f1d2c00,即eqIdbc60705b8d005d3ea47dd5ed13274de4,解得eqIdca542e78b7d77d008c9c4752afa91a55,故D.

故选:CD.

13eqId274a9dc37509f01c2606fb3086a46f4feqIdbdaa19de263700a15fcf213d64a8cd57

【分析】利用元素与集合关系得eqId7364f64bb956a50d43a42ce5dd40f242,再结合元素互异性求解即可

【详解】eqId2498d5578b17cadbf2c64e9eb763303b,故eqIdfcf1fc6b0dfeb3581e682bfd243a40db-2

经检验满足互异性

故填eqId274a9dc37509f01c2606fb3086a46f4feqIdbdaa19de263700a15fcf213d64a8cd57

【点睛】本题考查元素与集合的关系,注意互异性的检验,是基础题

14eqId09d7abf02717d6e59d8a64a65a87c412

【分析】利用基本不等式即可得到结果.

【详解】eqId16f3d198e76391779fa3badc848c8ac8eqIddc1d80797a6ada33ee435a586ebd52f0

eqIdbac869e1c428a391758933b57630ab9a

eqId06a35a1d3ac35b1dfcb5aa011efd2c24时,等号成立,其最大值为eqId09d7abf02717d6e59d8a64a65a87c412

故答案为:eqId09d7abf02717d6e59d8a64a65a87c412

15eqId9ad2f57dda9f8339766d9b7ffb3751d5

【分析】将原不等式化为eqId814d906c222e944498d4a7ed77f71ea5,再根据eqId0a6936d370d6a238a608ca56f87198de的取值范围,得到eqId0a6936d370d6a238a608ca56f87198deeqIda2c70fcaa661df4fbcad820b439accda的关系,从而得解;

【详解】解:原不等式即eqId814d906c222e944498d4a7ed77f71ea5

eqId7326ea56be82bd616fec7e6aa3c884c8,得eqId02437e5620037a29c83c685aabc5d123,所以eqId0e76495d144d3b234a586a009c228137

所以不等式的解集为eqId9ad2f57dda9f8339766d9b7ffb3751d5

故答案为:eqId9ad2f57dda9f8339766d9b7ffb3751d5

【点睛】本题考查含参的一元二次不等式的解法,属于基础题.

16eqId7cb905b363ea0e831a56e77ec434ebf4

【分析】由基本不等式求得eqId1cf99adccc80f28343fedd8d0aad7429的最小值,然后解相应的不等式可得eqId294f5ba74cdf695fc9a8a8e52f421328的范围.

【详解】eqId08115d6d9f876dea921a4d32260ff1fbeqId061813f1ec633c5c4c393c4de7938322,且eqId04645353d91a5beb6d02c06bb62683a9

eqIda1d194747cfb9fd0d9cb98a293242ec9

当且仅当eqIda8ea8932fbcb17a074f3601ce33940b7,即eqIde73288b61e1b77480fe983cfa0c70f94时等号成立,

eqId1cf99adccc80f28343fedd8d0aad7429的最小值为8

eqId63b507ee8a825378a1a70439f363e1f3解得eqIdd12b505d4a927602ab58dcc6abf024d5

实数eqId294f5ba74cdf695fc9a8a8e52f421328的取值范围是eqId7cb905b363ea0e831a56e77ec434ebf4

故答案为:eqId7cb905b363ea0e831a56e77ec434ebf4

【点睛】方法点睛:本题考查不等式恒成立问题,解题第一步是利用基本不等式求得eqId1cf99adccc80f28343fedd8d0aad7429的最小值eqId9e008ee8b0dc593ce21d8d4c87afef1c,第二步是解不等式eqIda8d91163b9e9aea5bff03bc2ed8d22a4

17(1)eqId8664d5ae12eced794c403f617ac91a5d

(2)eqIdb69ad3a2407cc385ad9e906cee42f65ceqId5d3d483587c95ec323e8fdd68f6f591b.

【分析】解一元二次不等式化简集合A,再利用交集的定义、补集的定义求解作答.

1

解不等式eqIde011b337fdb8459ca5006b772136c039得:eqId59569b8188e5493f2fda826546e6f701,而eqId5041bc91dc7835b2f9cb15bd950d4dd8

所以eqId3807920c91d1f38a966a6e184b13d4d3.

2

由(1)知eqIde9ff6362e2531816807263c3932af7d2eqIdb18d49782c83ea51587859d3c2bc216deqId55c040eddc0c4b8bbf15c2b539c7969ceqId5d3d483587c95ec323e8fdd68f6f591b

所以eqId422d018ef34d1c884737fd4df3d96d68eqId5d3d483587c95ec323e8fdd68f6f591b.

18(1)eqId38f81c6128dddaf4230324821feb43b6

(2)eqId6798fefbc8cb484060f97ffcc5340036

【分析】(1)若eqIdeaf140ea69179c08a3a4951d346deb84,则eqId21115ac52779c6e2054156e681985709,即eqIdf23d29646155e27b172ecdf263e2d702是方程eqId831c3990eff0d957ad589b6b07436d4b的根,由此求解即可;

2)因为eqId0b05d2be27e8f53e4de3071846dffb41,所以eqIdcaf22d7d1a965bda25168a233fb6290c,分情况讨论,求解即可.

1

因为eqId1086f72ebbb55737253b305b02184402,且eqIdeaf140ea69179c08a3a4951d346deb84

所以eqId21115ac52779c6e2054156e681985709,即eqIdf23d29646155e27b172ecdf263e2d702是方程eqId831c3990eff0d957ad589b6b07436d4b的根

所以eqIdfb558b6c44c4d14ec9cd9e5b8ee660f9,得eqIdea4a275ce5e652f3c82632c77f4bd9b0

eqIded3fe03015a1fc6ec62cee3e97c47654

所以eqIdfd4cbb837cbb30e0da9dde453ac6505a

2

因为eqId0b05d2be27e8f53e4de3071846dffb41,所以eqIdcaf22d7d1a965bda25168a233fb6290c

对于方程eqId831c3990eff0d957ad589b6b07436d4beqId8facf748782a77ea776065b997aa72b9

eqId197f80c90f0dc2985bc7e167028b85efeqId9105339cc1da9c8e712a0afc4747515e时,eqId5cf1e97de471ad174a6e9d4c41dafabc,满足eqId0b05d2be27e8f53e4de3071846dffb41

eqId34b1ca00d30c43416ba4dead30ebd7a7eqIdbf8eca68c4c7478f412183aa275fc7dceqId655b06387179d53c1e474fcfcb408b1e时,eqId928cd155cf20033821c58ab602111bd6

因为eqIdcaf22d7d1a965bda25168a233fb6290c,所以eqId4b135c01fab69e65b9ddf33235fcf244eqIde59d0f50469b3c28634fb32acb8390a8eqIdbca878f0d6e7766e3c662e8d0aa7b9f2

eqId4b135c01fab69e65b9ddf33235fcf244时,eqIdc6080dcd54db923f6998f5f2577b2a06,得eqId8e258ab9e600435b37465092243d99f6

eqIde59d0f50469b3c28634fb32acb8390a8时,eqId0db76d52cf62a42a222907b651dd9eae,无解

eqIdbca878f0d6e7766e3c662e8d0aa7b9f2时,eqId9801b960e74d77b7fd18e18453c1e616,无解

综上所述,eqId6798fefbc8cb484060f97ffcc5340036

19.(1eqId0b550ee821ee1838384835e81fc34b67;(2)答案见解析.

【分析】(1)由题意可得eqId9b384412acba251d87902ab928902f16eqId82b334dafda377c3db77647c8cf1e95f是方程eqId3a36808964ecf3cf1a0dff0ed28dc33b的两个根,根据韦达定理列方程即可求解;

2)若eqId03837b3769eda7f0d3804cc5ad4a6d60,不等式为eqIdcae76bbd9f35dcd97bdbfd7d4fa8d2c2,分别讨论eqId3b4d795709b0abcf47bceec2250f2f9beqId9e10e1c43b86a8cd4360ca9b57232164eqId606ef9cb8c9c4f61ab2acc4c11fec693eqId8e258ab9e600435b37465092243d99f6eqIdc6455e38ff53ede2508e4d9cb23f0b86解不等式即可求解.

【详解】(1)因为不等式eqId1f670cbb654f0f1dc28d0203d10d8fcd的解集为eqIdf20c78ad990e2424f4ece6a926e17baeeqIde8d5c65d76b90bafe1a009ef1693af2f

所以eqId9b384412acba251d87902ab928902f16eqId82b334dafda377c3db77647c8cf1e95f是方程eqId3a36808964ecf3cf1a0dff0ed28dc33b的两个根,

由根与系数关系得eqId9f77005e185c08e0eb540680984571ea,解得eqId0b550ee821ee1838384835e81fc34b67

2)当eqId03837b3769eda7f0d3804cc5ad4a6d60时,不等式为eqId1b6b870ab6fba18864f323d39975e588

eqId3b4d795709b0abcf47bceec2250f2f9b时,不等式为eqId722e44175566db7a0240651bd73ec6f0,可得:eqId7ccaa6e503b61e9ae78d8439cba2e328

eqId20849c00c47cbdc43f18d53341b6c4e5时,不等式可化为eqIdcae76bbd9f35dcd97bdbfd7d4fa8d2c2

方程eqId4935e1f6f4d5098cb18a1bcf0c37209b的两根为eqId87a60302649eb940748da818199e55daeqIdf99420a70b511c1907e0c25552d7925b

eqId9e10e1c43b86a8cd4360ca9b57232164时,可得:eqIdef954d1061ad24624eb9390b29455c88

eqId94440d3e4c073f94f2b266ff99d50e74时,

eqIdff1d468c29518f3ec7066248af0a1af8时,即eqIdc6455e38ff53ede2508e4d9cb23f0b86时,可得:eqId0fde64f4d3c38e43fbdee24eadc4b0ddeqId0e2e0bef54fa9ef481414ad163c6ca55

eqIdff44abf80dba43c3037e9537f32c3bf9eqId8e258ab9e600435b37465092243d99f6时,可得:eqId0e30c903d8f8a05332af0b19e7e40df3

eqId16a629fc5da04969bb1cea1505ca21c3,即eqId606ef9cb8c9c4f61ab2acc4c11fec693时,可得eqId7ccaa6e503b61e9ae78d8439cba2e328eqId96f31586b2e11c58ca9e343b51618def

综上:

eqId9e10e1c43b86a8cd4360ca9b57232164时,不等式解集为eqId350a30281ad81c9611bf880518c94c69

eqId3b4d795709b0abcf47bceec2250f2f9b时,不等式解集为eqId0d415c97598ae221e7bfaf95e3631021

eqId606ef9cb8c9c4f61ab2acc4c11fec693时,不等式解集为eqIdf20c78ad990e2424f4ece6a926e17baeeqId4c6dca136dbc1a7e628f4c5c45c1d9ed

eqId8e258ab9e600435b37465092243d99f6时,不等式解集为eqIddde86c3083ba8090da3dc2ee1c7fe37d

eqIdc6455e38ff53ede2508e4d9cb23f0b86时,不等式解集为eqId529cfb033abd4367b7f7f62c5988f1bdeqId4269c1c1a8eb144ec153519ad3b6b32f.

20(1)eqIdd2d89f74ade1b380747d247f0eed0da0

(2)eqId561800aa679a45da4dbe0e323de1fd59

【分析】(1)分eqIda882037b9ce104ecc496e0f31a139361eqId2f0d68648b10fce54dfc19c5ee60086deqId44a4eaa80b44625890339d6a0065c241三种情况讨论,当eqId44a4eaa80b44625890339d6a0065c241eqIdfc39e3f9688bc77675ffdf0dd79da142,即可求出参数的取值范围;

2)依题意可得eqIdc2ad78dc8b8aed907b4fe9640c997454,分eqIda347e53d69e6279105061e656d2f5bc7eqId52854d0ead4737302f4b4706e1f80553两种情况讨论,分别求出参数的取值范围,即可得解.

1

解:因为命题p不等式eqId4b6d03dfc5b4ce38e17403b3b49fdc15一切实数都成立是真命题,

eqIda882037b9ce104ecc496e0f31a139361时,eqId24decb3825c587420b9cca608609776a成立;当eqId2f0d68648b10fce54dfc19c5ee60086d时,不成立;

eqId44a4eaa80b44625890339d6a0065c241时,eqId25d1caed34ae16de055bbf3eb29d56d2,所以eqIdcd4720a60a4114fcb50d1c32613a57ab

综上所述,eqIdd2d89f74ade1b380747d247f0eed0da0

2

解:因为eqIddd9d50619b779c1056602f46b2a95e90,所以eqIdc2ad78dc8b8aed907b4fe9640c997454

由(1)可得eqIda5899ffbc9ecada886893aa20c52c52e

因为eqId7c27c6d191ae40039121e2a63d43bfe2

eqId7d39ff594fa24a569716ea9bf6fb3bc3,即eqId561800aa679a45da4dbe0e323de1fd59时,eqIda347e53d69e6279105061e656d2f5bc7,满足eqIddd9d50619b779c1056602f46b2a95e90

eqId0a475c485bc377f8d48be41a37ea28a6,即eqId17bda892497cea43df67db57b4e2a07a时,eqId52854d0ead4737302f4b4706e1f80553

eqIdc2ad78dc8b8aed907b4fe9640c997454,则eqId2102783b04b39f2216b1d31d0a9609fe,不等式组无解,

综上所述,eqId561800aa679a45da4dbe0e323de1fd59.

21(1)eqIdf89eef3148f2d4d09379767b4af69132

(2)eqIdc7e9b0d51e560b0e48fce28f95fcc3f6

【分析】(1)由基本不等式、完全平方公式即可eqIdb55e279e837b94cda37321e987861401的最小值;

2)根据不等式恒成立以及基本不等式“1”的代换可求a的取值范围.

1

因为eqId77633474efcd1a2f69a8c5e485b18ec2,有eqId1e3665ae3e78b755c2f344dc61bf0821

所以eqId6c1560eaaf18433f147d942a1d771121

当且仅当eqId9e29f37b0f4569325ee2eaf6d6118e16时,取等号,

所以eqId29ebc856291255f2d4a6c20b982a2442的最小值为eqIdf89eef3148f2d4d09379767b4af69132

2

eqIde4e454e09aaccf7fafc4f37ef79918aa恒成立,则eqIde168b1b9cacfa6113288dd09f0d0a473

因为eqId75804554569ade7f6337fc205194fec2

当且仅当eqIddd5ec61c33c44ec5e0134ff948133a68eqId906d7e20022e52d54f7ba52d00123266时,取等号,

所以eqIdf257b71e2b7886aadf7f1ebc809c10b1的最小值为9,即eqIdc8b43d4471892bd7b0cec0a139823cca

故实数a的取值范围是eqIdc7e9b0d51e560b0e48fce28f95fcc3f6

22(1)eqId7c1b4cc621ff98854b24ee610c05de91

(2)eqIdb8860d9787671b53b1ab68b3d526f5ca

(3)答案见解析

【分析】(1)分别在eqIdfd876a2ed79c64bacc3e64b8ee92735eeqId0baedc4d7e690ab3f7d80d30ba0a9efe的情况下,根据eqIdbfbeb3e2e09a14f1c05b9c30c4729f60恒成立可构造不等式组求得结果;

2)将所求式子化为eqId51920b302b1953c73f826de8060f3c43,利用基本不等式可求得最小值;

3)分别在eqIdfd876a2ed79c64bacc3e64b8ee92735eeqId58b140e221ddf537b8964fff8557cca0eqIdfa204d6b5183969f6da37f369eb7293deqId7aed39f5aca78934fb383402433fe549eqId232961f0b0cbe58baf7522762876dfbc的情况下,解不等式即可得到结果.

1

eqId1e59bb4bf2e0698d876cf815362b3658恒成立得:eqIdbfbeb3e2e09a14f1c05b9c30c4729f60对一切实数eqId81dea63b8ce3e51adf66cf7b9982a248恒成立;

eqIdfd876a2ed79c64bacc3e64b8ee92735e时,不等式为eqIda6e2e79843faf62dde86bf858d1e0569,不合题意;

eqId0baedc4d7e690ab3f7d80d30ba0a9efe时,eqIdddb596e75510177513df49535f032a89,解得:eqId04dd738318785c28ab61db28378cb9c1

综上所述:实数eqId294f5ba74cdf695fc9a8a8e52f421328的取值范围为eqId7c1b4cc621ff98854b24ee610c05de91.

2

eqIdac65b9d7c97989f7429f63bc27caaaedeqIda7ad273857e023fe2ce254c059ad7c36

eqId4bfcafec284662eb76fa42e449cd90e9(当且仅当eqIdceaea42f01469897dea1fa139d44d57a,即eqIdcf0086b054ef120408acac806a1b1318时取等号),

eqId75dc5265678aa8eeb981867018d91db1的最小值为eqIdb8860d9787671b53b1ab68b3d526f5ca.

3

eqId707512cd486582a6cf3de9858c592d17得:eqId2f92a5cca4ef4a2900b4c67dfae6b8e2

eqIdfd876a2ed79c64bacc3e64b8ee92735e时,eqId463cedbf92bbf7c870860d06208ea81f,解得:eqId7ccaa6e503b61e9ae78d8439cba2e328,即不等式解集为eqId9b4280adea02588850b0a1af4844fcea

eqId0baedc4d7e690ab3f7d80d30ba0a9efe时,令eqId69a73f45730bb6ac9f91a85c72ab4cd6,解得:eqId87a60302649eb940748da818199e55daeqId5ed1e5772cb8c934b5b64aa992de2c24

i)当eqId324d1e995cfbed169688b7de79ae097d,即eqId58b140e221ddf537b8964fff8557cca0时,不等式解集为eqId7e95e5bd0f4fb87f92a166860c6d2572

ii)当eqIdfc5fe3dabeabddfaf774113e77e0dc54,即eqIdfa204d6b5183969f6da37f369eb7293d时,不等式解集为eqIdd544f05ae3b0471ea95306efadeb25c7

iii)当eqId02d7580bae50f1b1b779ad066b164bb4,即eqId7aed39f5aca78934fb383402433fe549时,不等式可化为eqIde74f2897cababb5fe9b9355119158dd1eqIdf3d700f6166a5203d204b2123765bc25

eqId2de0d10ef8b748d4531250c37c5d3f9e不等式解集为eqIdf0f550665c6921f4af67e3f01a563394

iv)当eqId0719ec891d82aada8927821b4cc03f82,即eqId232961f0b0cbe58baf7522762876dfbc时,不等式解集为eqIdf0de79d373340c25627a50cc65186e8f

综上所述:当eqIdfd876a2ed79c64bacc3e64b8ee92735e时,不等式解集为eqId9b4280adea02588850b0a1af4844fcea;当eqId58b140e221ddf537b8964fff8557cca0时,不等式解集为eqId7e95e5bd0f4fb87f92a166860c6d2572;当eqIdfa204d6b5183969f6da37f369eb7293d时,不等式解集为eqIdd544f05ae3b0471ea95306efadeb25c7;当eqId7aed39f5aca78934fb383402433fe549时,不等式解集为eqIdf0f550665c6921f4af67e3f01a563394;当eqId232961f0b0cbe58baf7522762876dfbc时,不等式解集为eqIdf0de79d373340c25627a50cc65186e8f.

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