2024·全国·模拟预测
解题方法
1 . 在解决问题“已知正实数
满足
,求
的取值范围”时,可通过重新组合,利用基本不等式构造关于
的不等式,通过解不等式求范围.具体解答如下:
由
,得
,即
,解得
的取值范围是
.
请参考上述方法,求解以下问题:
已知正实数
满足
,则
的取值范围是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb975603433961a27ff01c734d39575f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f29d5f376c75c41ae6af0c8a8565449.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f29d5f376c75c41ae6af0c8a8565449.png)
由
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d14a76fbd7733394b3a7a8c7508ae8f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09a2ebb75f6dc5ba596a98ccbc2bb9be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef066cf9a851361e923ed40c97b842.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f29d5f376c75c41ae6af0c8a8565449.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eed05aa46ec16ee8f98272565d2a2ed9.png)
请参考上述方法,求解以下问题:
已知正实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb975603433961a27ff01c734d39575f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e7bf9200b351a259ddfc6c0266129d.png)
您最近一年使用:0次
2 . 牛顿迭代法是我们求方程近似解的重要方法.对于非线性可导函数
在
附近一点的函数值可用
代替,该函数零点更逼近方程的解,以此法连续迭代,可快速求得合适精度的方程近似解.利用这个方法,解方程
,选取初始值
,在下面四个选项中最佳近似解为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79b752f0f189e5d8666daea73e145dff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4288ce7da394135a8c5b0b067d384d09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910717f3df9f31b0ff377f65a16a4ca5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e099a6abe3e9566b2ad385906e323fc.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
3 . 根据多元微分求条件极值理论,要求二元函数
在约束条件
的可能极值点,首先构造出一个拉格朗日辅助函数
,其中
为拉格朗日系数.分别对
中的
部分求导,并使之为0,得到三个方程组,如下:
,解此方程组,得出解
,就是二元函数
在约束条件
的可能极值点.
的值代入到
中即为极值.
补充说明:【例】求函数
关于变量
的导数.即:将变量
当做常数,即:
,下标加上
,代表对自变量x进行求导.即拉格朗日乘数法方程组之中的
表示分别对
进行求导.
(1)求函数
关于变量
的导数并求当
处的导数值.
(2)利用拉格朗日乘数法求:设实数
满足
,求
的最大值.
(3)①若
为实数,且
,证明:
.
②设
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4a1d0dba29a77dd111efcde543d6c1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc4c14935585e8fa61d032730867d771.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67b6f154c6b2de5695eb1807b98c2c63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/809615d1f91508e2c6c0cda7e592c479.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/244021f826099b18e31af1143597bba2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb5be11a5e6aaf00b2833930b198b4cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0203b006524305c3d8ee0b6c34cd872b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4a1d0dba29a77dd111efcde543d6c1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc4c14935585e8fa61d032730867d771.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1c3c1ed4fb65ab9505ad8078d8d0fb5.png)
补充说明:【例】求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d7ca0caa9933b7afd4bed2683140a07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aebdee8d81b048b5aa520f7e8ba56ff2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1e15a54c6122c695239107dd0901bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/244021f826099b18e31af1143597bba2.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b3d9ab2fcf15b94f33cb64f84ed906c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b384412acba251d87902ab928902f16.png)
(2)利用拉格朗日乘数法求:设实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c45d8122b61de13875003d00c002c5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de725a9fc66f67abbe0015131846a648.png)
(3)①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a14c388e1e2e5a2ff1ccf6caffbee0d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd24c686fbaaa68705d654b880481ffe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e778f95c72fec00bfbbc63e6dfd0c460.png)
②设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/497d269c30eec393e3f0e877ddbe2983.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ade042c085bbad8aeaf111b9f4c33408.png)
您最近一年使用:0次
解题方法
4 . 在组合恒等式的证明中,构造一个具体的计数模型从而证明组合恒等式的方法叫做组合分析法,该方法体现了数学的简洁美,我们将通过如下的例子感受其妙处所在.
(1)对于
元一次方程
,试求其正整数解的个数;
(2)对于
元一次方程组
,试求其非负整数解的个数;
(3)证明:
(可不使用组合分析法证明).
注:
与
可视为二元一次方程的两组不同解.
(1)对于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/114b84ba3234b9bb1bf9f64c172292d7.png)
(2)对于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa38e21db62123319c9557d1bc52825d.png)
(3)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d63a043e64f7ed5d168cd2c9384e953b.png)
注:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65fe832c0460e00120d4bc3636aebcaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa6c8fe63bb58df1c5a12422e9c9e291.png)
您最近一年使用:0次
2024-03-08更新
|
1113次组卷
|
3卷引用:广东省五粤名校联盟2024届高三第一次联考数学试题
5 . “黄金分割”是古希腊的毕达哥拉斯学派在研究数学问题时提出的一个比例关系,即:将一线段分割成大小两段,如果小段与大段的长度之比恰好等于大段与整段的长度之比,那么称这个比值为“黄金分割比”,经常用希腊字母
来表示.在数学中也可用无穷连分数
(其中“…”代表无限次重复)来表示“黄金分割比”,它可以通过方程
解得
,即黄金分割比为
.类比上述过程,计算式子
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37502db587be8f665f851e952162ae2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34171e130641b4c17fe9c659be63d14e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a31a869c72e1330b2e12716ddd0b8e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c86cb753ef281db76db9f9fffea1a998.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/029d393bb07b7140905b85f550519de4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3f4d0c458d8751f5d19e8a44fc97315.png)
A.1 | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2021-07-01更新
|
377次组卷
|
3卷引用:吉林省吉林市2019届高三数学(文)第四次调研试题
名校
解题方法
6 . 利用方程的方法可以将无限循环小数化为分数,例如将
化为分数是这样计算的:设
,则
,即
,解得
.
这是一种利用方程求解具有无限过程的问题的方法,这种方法在高中计算无限概率、无限期望问题时都有很好的妙用.
已知甲、乙两人进行乒乓球比赛,每局比赛甲获胜的概率为
,乙获胜的概率为
,每局比赛的结果互不影响.规定:净胜
局指的是一方比另一方多胜
局.
(1)如果约定先获得净胜两局者获胜,求恰好4局结束比赛的概率;
(2)如果约定先获得净胜三局者获胜,那么在比赛过程中,甲可能净胜
局.设甲在净胜
局时,继续比赛甲获胜的概率为
,比赛结束(甲、乙有一方先净胜三局)时需进行的局数为
,期望为
.
①求甲获胜的概率
;
②求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f522d1f7a4158bbb09355fcf2ebe1748.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd96b78172b97a5fb995bc4fe7a91312.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c9a257d22b01103a676795f6a6b399e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8567750e1eb0471c3942c1456cdf2299.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fae7b60887e1ae9ff3f6b2b959762e.png)
这是一种利用方程求解具有无限过程的问题的方法,这种方法在高中计算无限概率、无限期望问题时都有很好的妙用.
已知甲、乙两人进行乒乓球比赛,每局比赛甲获胜的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(1)如果约定先获得净胜两局者获胜,求恰好4局结束比赛的概率;
(2)如果约定先获得净胜三局者获胜,那么在比赛过程中,甲可能净胜
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68061f9674fb257c62da194bebd65289.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59c709117ab1d3ef620883a732aed68b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f95e54a9b7c66c97dc6ee6161a25c0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56b678dec65a0ca8006cc6828d8cb501.png)
①求甲获胜的概率
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf9f50605db5d5f8f3a01ee8e474a112.png)
②求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fc8a872d7b16187634e8db2571c8cbe.png)
您最近一年使用:0次
2024-06-09更新
|
1297次组卷
|
2卷引用:湖北省武汉市武昌区2024届高三下学期5月质量检测数学试卷
解题方法
7 . 大力开展体育运动,增强学生体质,是学校教育的重要目标之一.某校组织全校学生进行了立定跳远训练,为了解训练的效果,从该校男生中随机抽出100人进行立定跳远达标测试,成绩(单位:米)均在
内,整理数据得到如下频率分布直方图.学校规定男生立定跳远2.05米及以上为达标,否则不达标.
![](https://img.xkw.com/dksih/QBM/2022/5/7/2974373271633920/2975164936478720/STEM/e78eef27-5c24-4fa7-b5f5-c354c5e6b86b.png?resizew=397)
(1)若男生立定跳远的达标率低于60%,该校男生还需加强立定跳远训练.请你通过计算,判断该校男生是否还需加强立定跳远训练;
(2)从该校随机抽取的100名立定跳远成绩在
和
内的男生中,用分层抽样的方法抽取7人,再从这7人中随机抽取2人,求这2人来自不同区间的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/613af564447c34564fc04450a28598f1.png)
![](https://img.xkw.com/dksih/QBM/2022/5/7/2974373271633920/2975164936478720/STEM/e78eef27-5c24-4fa7-b5f5-c354c5e6b86b.png?resizew=397)
(1)若男生立定跳远的达标率低于60%,该校男生还需加强立定跳远训练.请你通过计算,判断该校男生是否还需加强立定跳远训练;
(2)从该校随机抽取的100名立定跳远成绩在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6da010cdabd6762d8a7796310589c51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e32dd67dd6517fc1079a71945d0682d.png)
您最近一年使用:0次
8 . 已知
,不等式
恒成立.
(1)求
的值
;
(2)若方程
有且仅有一个实数解,求ab的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a788b2d8cce011455e549a59ebc5c92b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ce9dc4b97804d00d682fed1b04a7eb0.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34a8eb19e30aa486abf1b0dfb3d3bd6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)若方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c5cbe4c9cd2831801f4a564641b8d90.png)
您最近一年使用:0次
解题方法
9 . 1799年,哥廷根大学的高斯在其博士论文中证明了如下定理:任何复系数一元
次多项式方程在复数域上至少有一根(
).此定理被称为代数基本定理,在代数乃至整个数学中起着基础作用.由此定理还可以推出以下重要结论:
次复系数多项式方程在复数域内有且只有
个根(重根按重数计算).对于
次复系数多项式
,其中
,
,
,若方程
有
个复根
,则有如下的高阶韦达定理:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68be203b2490ecce4c0e2eadeb5d911b.png)
(1)在复数域内解方程
;
(2)若三次方程
的三个根分别是
,
,
(
为虚数单位),求
,
,
的值;
(3)在
的多项式
中,已知
,
,
,
为非零实数,且方程
的根恰好全是正实数,求出该方程的所有根(用含
的式子表示).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e167b43045b3297248e334c41c621b8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b024d78f428194127b5534f948810def.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7230de53663c75658c58bbf206a0085.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bed25da42194b5a81d123933d5704f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd3759b3561834cdc5b499b91f3850d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86b92b70365c63607daecdc8deb73ecf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c83590c4a7ea5636843dd4b60c67cb40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68be203b2490ecce4c0e2eadeb5d911b.png)
(1)在复数域内解方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4800c5aa0e5b70b2141541cbd3853e34.png)
(2)若三次方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac603c0b3d1d7fd42bd50222b6ab94d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6755cd39b121a0dd2a14da8d43c1fff4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ddb97874a62bb5530514a467d64af13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8079c5a2d8674d322f7abe6d4ef4a3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a7035cd4adda5d72a9fc9f9fda75995.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
(3)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5818ede14d21f6df9ef9c2bfe09286c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b024d78f428194127b5534f948810def.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cb3db0a99f86232e0cf3e55c789ea99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e2e2674707c28eddd3f3ab60f73f54f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c37d6353f394a5704a92113908a5c3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86b92b70365c63607daecdc8deb73ecf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
您最近一年使用:0次
10 . 九连环是中国一种古老的智力游戏,其结构如图,玩九连环就是要把这九个环全部从框架上解下或套上.研究发现,要解下第
个环,则必须先解下前面第
个环.用
表示解下
个环所需最少移动次数,用
表示前
个环都已经解下后,再解下第
个环所需次数,显然,
,
,且
.若要将第
个环解下,则必须先将第
个环套回框架,这个过程需要移动
次,这时再移动1次,就可以解下第
个环;然后再将第
个环解下,又需要移动
次.由此可得,
.据此计算![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2cd47b30a15a6ace20e2fc840a9add.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8c66acb7fc592b8474ab3f9d40a3590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e345e86daf74312a6992e5d1c3f47f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/702353dcd94e65036a199deced89f8a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c0cdbf7b7cb42491810101c6e0db4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd310a4c39f1522cafacf1aeae19c3c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e181cdd42105f02e1a4446054ae65d34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96ae7d749ab38b1b10e27a535719e673.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c0cdbf7b7cb42491810101c6e0db4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/908953401be1d145ed967572c8f6b753.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c0cdbf7b7cb42491810101c6e0db4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/908953401be1d145ed967572c8f6b753.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7c07ac0804045aca56d41c17ee80ae2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2cd47b30a15a6ace20e2fc840a9add.png)
您最近一年使用:0次