(1)如图1,已知正方形
的边长为4.点M和N分别从点B、C同时出发,以相同的速度沿
、
方向向终点C和D运动.连接
和
,交于点P.
①猜想
与
的位置关系,并证明你的结论.
②求运动过程中,线段
扫过的面积.
(2)如图2,已知菱形
的对角线
为
,
.点M和N分别从点B、C同时出发,以相同的速度沿
、
向终点C和A运动.连接
和
,交于点P.求
周长的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1ffb98f1e3c1317c0db403d3af04bdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07377d977ef6a8f518b3004564544e5b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/14/8287f449-aa4a-4493-9b5b-1090c98abb0c.png?resizew=104)
①猜想
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07377d977ef6a8f518b3004564544e5b.png)
②求运动过程中,线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80672dda9430cb42b3136bcb1b67bbad.png)
(2)如图2,已知菱形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a9c6a736e6eac98a676fa3232db5a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38387ba1cadfd3dfc4dea4ca9f613cea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e853863d4da6b10d69ba5a8893c6f8d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14b49022a6f55817b5d7e3ab443b5491.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07377d977ef6a8f518b3004564544e5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af2cc5f8cec8c498aa12c99c04e1c97d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/14/d103035f-99a2-4324-b9f1-28e52ff9b965.png?resizew=171)
更新时间:2023-06-12 18:39:28
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相似题推荐
解答题-问答题
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【推荐1】如图1,在菱形ABCD中,∠B为锐角,点P,H分别在边AD,CB上,且
,在AB边上取点M,N(点N在BM之间)使AM=5BN,点P从点D匀速运动到点A时,点Q恰好从点M匀速运动到点N,连结PQ,PH分别交对角线AC于E,F,记QN=x,QP=y,已知
.
![](https://img.xkw.com/dksih/QBM/2021/12/20/2876432655278080/2942388877844480/STEM/114f95b1-aa13-4ace-8a16-270c0d9d4ea6.png?resizew=342)
(1)①请判断PF与FH的大小关系,并说明理由;
②求AD,BN的长;
(2)如图2,连结QF,当四边形FQBH中有两边平行时,求AE∶EC的值;
(3)若
,连结QH,求△FQH面积的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1fd28c83ee0751d7e1f3fb6d4b90193.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dab8aa8c8873b8175813273a6b6556bb.png)
![](https://img.xkw.com/dksih/QBM/2021/12/20/2876432655278080/2942388877844480/STEM/114f95b1-aa13-4ace-8a16-270c0d9d4ea6.png?resizew=342)
(1)①请判断PF与FH的大小关系,并说明理由;
②求AD,BN的长;
(2)如图2,连结QF,当四边形FQBH中有两边平行时,求AE∶EC的值;
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/784d093b48df0ba4ae15ea1368fe85e8.png)
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解答题-作图题
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【推荐2】综合与实践
数学活动课上,同学们用尺规作图法探究在菱形内部作一点到该菱形三个顶点的距离相等.
【动手操作]如图,已知菱形
,求作点E,使得点E到三个顶点A,D,C的距离相等.小红同学设计如下作图步骤∶
;
②分别以点A,D为圆心,大于
的长为半径分别在
的上方与下方作弧:
上方两弧交于点M,下方两弧交于点N,作直线
交
于点E.
③连接
,
,则
.
(1)根据小红同学设计的尺规作图步骤,在题图中完成作图过程(要求∶用尺规作图并保留作图痕迹)
(2)[证明结论]证明:
.
(3)[拓展延伸]当
时,求
与
的面积比.
数学活动课上,同学们用尺规作图法探究在菱形内部作一点到该菱形三个顶点的距离相等.
【动手操作]如图,已知菱形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
②分别以点A,D为圆心,大于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4cb1a4c5afb590c7c17de14d15651e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
③连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c21fe43b8bfca2c3adb758c1697905fe.png)
(1)根据小红同学设计的尺规作图步骤,在题图中完成作图过程(要求∶用尺规作图并保留作图痕迹)
(2)[证明结论]证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c21fe43b8bfca2c3adb758c1697905fe.png)
(3)[拓展延伸]当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3104c05e255396a91038e2896aedf5cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6818a98204f62c1b16699d26ca0c3f62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cb3e973f4e9361e1d23a0ab56006d12.png)
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名校
【推荐1】如图,正方形ABCD的对角线相交于点O.点E是线段DO上一点,连接CE.点F是
的平分线上一点,且
与CO相交于点G.点H是线段CE上一点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/15/19e18506-1a04-49b6-8ba4-bc1119407639.png?resizew=154)
(1)若
,求FH的长;
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce77e9b3018db01b344ee975dfa21d04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a989aa942219970ec11ccd6ab186d69b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3094e2918186de8aed69c64690c444b2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/15/19e18506-1a04-49b6-8ba4-bc1119407639.png?resizew=154)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c339b0e700b7eef33972441df06faa6.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/633f9d0098f943f1266b580b69234570.png)
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【推荐2】【问题情境】数学课上,王老师出示了这样一个问题:如图1,在矩形
中,
,
是
延长线上一点,且
,连接
,交
于点
,以
为一边在
的左下方作正方形
,连接
.试判断线段
与
的位置关系.
(1)【探究展示】小明发现,
垂直平分
,并展示了如下的证明方法:
证明:∵
,
∴
.
∵
,
∴
.
∵四边形
是矩形,
∴
.
∴__________.(平行线分线段成比例)
∵
,
∴
.
∴
.
即
是
的
边上的中线,
又![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
∴__________.(等腰三角形的“三线合一”)
∴
垂直平分
.
请将上述证明过程补充完整;
(2)【反思交流】
小颖受到小明的启发,继续进行探究,如图2,连接
,以
为一边在
的左下方作正方表
,发现点
在线段
的垂直平份线上,请你给出证明;
(3)【拓展应用】
如图3,连接
,以
为一边在
的右上方作正方形
,分别以点
,
圆心,
为半径作弧,两弧交于点
,连接
.若
,请直接写出
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b929269c53a44907dba8ee298a0a522.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e92f48e9bfe12d145f7d2a2f0360d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2257da1e2425f2ea9ac7440f52659ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/22/f230059e-05bc-4b35-8c79-51bad923baf1.jpg?resizew=480)
(1)【探究展示】小明发现,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e92f48e9bfe12d145f7d2a2f0360d0.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/019a351c8982e78e7c69503880e2f7a2.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b929269c53a44907dba8ee298a0a522.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
∵四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
∴__________.(平行线分线段成比例)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e92f48e9bfe12d145f7d2a2f0360d0.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/479b9cd3d4a1c6707a7dc608734d4f44.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4796a77ffd026046b8eefd50938830a2.png)
即
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
∴__________.(等腰三角形的“三线合一”)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
请将上述证明过程补充完整;
(2)【反思交流】
小颖受到小明的启发,继续进行探究,如图2,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1f13007c6d134c50004c62dc240707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(3)【拓展应用】
如图3,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1f13007c6d134c50004c62dc240707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d5147cea4c9ce855074864fe54506.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c2e34bbbc4af1fe2a35009aae67e251.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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解答题-证明题
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真题
【推荐1】如图,△ABC和△ABD都是⊙O的内接三角形,圆心O在边AB上,边AD分别与BC,OC交于E,F两点,点C为
的中点.
![](https://img.xkw.com/dksih/QBM/2012/8/3/1573476199489536/1573476224720896/STEM/2b1eb017f1df4f258774c5b2aea95f94.png)
(1)求证:OF∥BD;
(2)若
,且⊙O的半径R=6cm.①求证:点F为线段OC的中点; ②求图中阴影部分(弓形)的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cabb7676b41c853ae8d7ffe5bf11376f.png)
![](https://img.xkw.com/dksih/QBM/2012/8/3/1573476199489536/1573476224720896/STEM/2b1eb017f1df4f258774c5b2aea95f94.png)
(1)求证:OF∥BD;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dbfc7a956ce54292a6cd60af887691c.png)
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【推荐2】如图,以△ABC的BC边上一点O为圆心的圆,经过A、B两点,且与BC边交于点E,DO⊥BE于点O,连接AD交BC于F,若AC=FC.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/27/3f60350c-f81f-41d8-9edf-8a5c2511c9c1.png?resizew=265)
(1)求证:AC是⊙O的切线:
(2)若BF=8,DF=
,求⊙O的半径;
(3)若∠ADB=60°,BD=1,求阴影部分的面积.(结果保留根号)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/27/3f60350c-f81f-41d8-9edf-8a5c2511c9c1.png?resizew=265)
(1)求证:AC是⊙O的切线:
(2)若BF=8,DF=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60cbb271baca5cd015f30e07d9eebfd8.png)
(3)若∠ADB=60°,BD=1,求阴影部分的面积.(结果保留根号)
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【推荐1】如图,C为
外一点,连接
、
、
,过点A作
,
.
(1)求证:
.
(2)若
,求证:
.
(3)在(2)的条件下,
,
,
,求
长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e3f5dc11efe60b4fd9a13b1d6b83842.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a702c324e0c76150540c3d32df802077.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/20/e9adc303-7f17-42e3-bc89-b053460a0dd8.png?resizew=152)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/328ac471f7b27c38c4428ea66d5c5d7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c1016bc9ef1c728bccf070a6e4a532f.png)
(3)在(2)的条件下,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1a21782163ade7050baa9b96b22c196.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa18c2a78c400c80a5760743f31771c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54275b7e571660d0a9e0370fbfe5050b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
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解答题-问答题
|
较难
(0.4)
【推荐2】如图,半径为4的扇形
中,
,C为弧
上的一个动点(点C不与点A,B重合),过圆心O分别作弦
,
的垂线
,
,垂足分别为D,E.
的度数;
(2)当点C沿着弧
从点A出发,顺时针运动到点B时,求
的外心P所经过的路径的长度;
(3)设
,
,连接
,分别交
,
于点M,N,记以线段
,
,
为三边的三角形的外接圆半径为r,当四边形
的面积取最大值时,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a77343ecde1c2665df291761b6563.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ccc37b189fa2cbc269ca0b233dac37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a299d2b999568e80be8005565ba209a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cbee6d5731d6f4bb1e4f2ba3d89b7dc.png)
(2)当点C沿着弧
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32e00bf73d03dded1cf5f83cc5339361.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3d296e0d7154a170cb7d3ae42989b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4a88b719166fcc1431f876bc8c5656c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a299d2b999568e80be8005565ba209a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/279563c3c055777ce1aa369a2ef54aed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c65064ac7afe010aa20af8640859519.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4ac5dbc0bc2e97fd393e6eca936738b.png)
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