如图,圆形纸片的圆心为
,半径为
,该纸片上的正方形
的中心为
,
、
、
、
为圆
上点,
,
,
,
分别是以
,
,
,
为底边的等腰三角形,沿虚线剪开后,分别以
,
,
,
为折痕折起
,
,
,
,使得
、
、
、
重合,得到四棱锥.当该四棱锥体积取得最大值时,正方形
的边长为______
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/244ea6a312d4b6831a6b833ea3f4fcd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fee50575e3ebd56c4f46dd0bbf8e55d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbda7249e6387d4a0ad11595883a584f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f12cc84355f5585d1e3d12dde4e0c795.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc6c92562ed4769af22da8b6d1006d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a96239564d22c91aaa0f9f78cf487a25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.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/67d822262ff00915910e5b87d81ad1ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.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/67d822262ff00915910e5b87d81ad1ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbda7249e6387d4a0ad11595883a584f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f12cc84355f5585d1e3d12dde4e0c795.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc6c92562ed4769af22da8b6d1006d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a96239564d22c91aaa0f9f78cf487a25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fee50575e3ebd56c4f46dd0bbf8e55d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97153bc3d02dfb38ee046487a8037a41.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/3ca4eaa7-9a51-4a38-b844-44e0b30674d6.png?resizew=170)
更新时间:2019-12-30 16:12:23
|
相似题推荐
填空题-单空题
|
适中
(0.65)
名校
解题方法
【推荐1】已知函数
在区间
上有零点,则
的最小值为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42665f44e79bcdaf385a493e0f25e641.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7242b2ab643f9470da77e29d043b893.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83ea412665e3af61cb99cc3cd4764e60.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
【推荐2】已知函数
是定义在
上的奇函数,满足
,
,且
在
内恒成立(
为
的导函数),若不等式
恒成立,则实数
的取值范围为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c956729663fad34fb571842fb89b4483.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09fbb68bd262a20e0b850de06bc08f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f07bcef066296be983c61e77a9154e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f00f2f6ab162f9333ec55db195d663b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/724340d69477c0ec2418c392b22b1cab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cccf32e038a96345e39b400fa2fad28.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
解题方法
【推荐3】(1)已知向量
的夹角为
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34007d1704c61c9b14e5f531c6dbd033.png)
________ .
(2)已知
中,内角
的对边分别为
,若
,则
的面积为_____________ .
(3)已知函数
,则
的最小值是_____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/116e2e7116a7b5cd0a912ec0699ca017.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d5bca00fa20e6e80480b9d06d2e52ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e2de0282b57de0e1806651fc3c94e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34007d1704c61c9b14e5f531c6dbd033.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/381b9b520918a84b1035b7489ee32776.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(3)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f1c1b2f0b0e19039543ac23775784cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
解题方法
【推荐1】三棱锥
中,
平面
,
为正三角形,外接球表面积为
,则三棱锥
的体积
的最大值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cb9c018281fcaaf52863e1f83d9dad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd689863203d6891a6a8ce8b40dd5a90.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
【推荐2】已知一个母线长
米的圆锥形容器,则当该容器的容积最大时,其高为___________ 米.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adbd3e8cf8325999cde03adf845d3dd0.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
【推荐1】如图所示的几何体中,四边形
是矩形,平面
平面
,已知
,
,且当规定正视图方向垂直平面
时,该几何体的左视图面积为
,若
、
分别是线段
、
上的点,则
的最小值为_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7477fccf4400c9c654e4fe3477032ad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4efa274c6df72d4b978cf38c6db4fef.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/19/8b86339a-ca30-47bf-930f-1f2e1c2332d2.png?resizew=149)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
解题方法
【推荐2】已知正四棱锥
的所有棱长均为
,E,F分别是PC,AB的中点,M为棱PB上异于P,B的一动点,则
的最小值为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67f4e39b200f9656e532bcb5ab78cb86.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
【推荐1】正方体AC1棱长是1,点E、F是线段DD1,BC1上的动点,则三棱锥E一AA1F体积为___ .
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
解题方法
【推荐2】如图,在正方体
中,
是线段
上的动点,下列四个结论:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/183d2833-8785-4fb8-80a5-96bfe8afaf95.png?resizew=168)
①
面
;
②
面
;
③直线AD与平面
所成角的正弦值为
;
④三棱锥
的体积不变.
其中正确结论的序号为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/183d2833-8785-4fb8-80a5-96bfe8afaf95.png?resizew=168)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d560542b646924eaf577480ac73281b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da7977ab975efa6411cc17de39be70d9.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/565133e91e3ace2b2187cfc6f1db5be6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da7977ab975efa6411cc17de39be70d9.png)
③直线AD与平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da7977ab975efa6411cc17de39be70d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1174142f3bba761585b6bc2653009b36.png)
④三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96a91c2d02c8116e99111c488056553d.png)
其中正确结论的序号为
您最近一年使用:0次