如图,在三棱锥
中,
,
平面
,
,
分别为棱
,
的中点.
![](https://img.xkw.com/dksih/QBM/2022/2/16/2917543383539712/2921253201666048/STEM/4cd6de5df03d46b5ab82216b6ae05f2d.png?resizew=196)
(1)求证:
;
(2)若
,
,二面角
的大小为
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b714ae78e40471842536db2bdd29a45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.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/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://img.xkw.com/dksih/QBM/2022/2/16/2917543383539712/2921253201666048/STEM/4cd6de5df03d46b5ab82216b6ae05f2d.png?resizew=196)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34b416412f982d9c6956b2229d6e3729.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06201e4f55b78d8b30afb257d5a1b16b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb5b12692517a39c320f99a479eb055.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/141df7ba990794bca216541dfe4ccc55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6b86c22b670a8e9f3896f9e8883fbbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
更新时间:2022-02-21 16:47:45
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,已知三棱锥
中,
,
,
为
的中点,
为
的中点,且
为正三角形.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/16e234c3-c1c3-4afe-879b-d613fa46c470.png?resizew=152)
(1)求证:
平面
;
(2)求证:
平面
;
(3)若
,
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42a2e72e4d5afb3d8b4aba4938a8814e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dee6c1410e79934b560642684807e70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cbfbedd45e9f0b994bfcd51e0376fc3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/16e234c3-c1c3-4afe-879b-d613fa46c470.png?resizew=152)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ba8f7af0e091e082100c3cd7f8c487f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65a3e478bb87d094e3a0af30dd10ae8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc34db5860990e51ba31edc8cdd077c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/076fdb31d17c86dbdc53da175c6ae90b.png)
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解题方法
【推荐2】如图1,与三角形的三边都相切的圆叫做三角形的内切圆.设O是△ABC的内切圆圆心,r是△ABC的内切圆半径,设S是△ABC的面积,l是△ABC的周长,由等面积法,可以得到.
(1)与三棱锥的四个面都相切的球叫做三棱锥的内切球.设三棱锥的体积是V,表面积是S,请用类比推理思想,写出三棱锥的内切球的半径公式R内(只写结论即可,不必写推理过程);
(2)若多面体的所有顶点都在同一球上,则该球为多面体的外接球,如图2,在三棱锥P-ABC中,PA,PB,PC两两垂直,且PA = PB = PC = 1,求三棱锥P-ABC的内切球半径和外接球的半径.
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【推荐1】如图所示,菱形
的对角线
与
交于点
,
,将
沿
翻折到
的位置,使得
.
![](https://img.xkw.com/dksih/QBM/2021/7/10/2761152038019072/2777292968050688/STEM/93032b7b-df47-44a8-ba6a-963dc9ed3b57.png?resizew=321)
(1)求证:平面
平面
;
(2)当
时,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c3e9ef3e849788645552cfb0735d987.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3ea25ef38e4afa8f75ffd0842890289.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a67d8576417f761dd5f583ad3a1555a8.png)
![](https://img.xkw.com/dksih/QBM/2021/7/10/2761152038019072/2777292968050688/STEM/93032b7b-df47-44a8-ba6a-963dc9ed3b57.png?resizew=321)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fe052786101dfcc941480919eb2cecc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcd31cebdaf8db5222da9256db1a40c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1e2b526ff361f7771caf5d8411e96b0.png)
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【推荐2】已知五面体
中,四边形
为矩形,
,
,且二面角
的大小为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/8/2bc9ccf7-71ed-4933-9b3f-ebdf690688d5.png?resizew=247)
(1)证明:
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e837903cd04ec7243ac456cb9d94d4e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/025df2a9934b457cf20d91604e430612.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3e9d395e5501c87fec93dee44d24027.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/996bf3d35b6763cbc1a423b13a9df2dd.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/8/2bc9ccf7-71ed-4933-9b3f-ebdf690688d5.png?resizew=247)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a8d99c75180422fecf6d3f3d2910b34.png)
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【推荐3】如图,在四棱锥
中,底面ABCD是边长为4的正方形,侧面APD是以AP为斜边的直角三角形,且平面
平面APC.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/15/baeddbf3-eb06-4783-a66e-49338a7b618d.png?resizew=165)
(1)求证:
平面PAD;
(2)若M为PA的中点,且
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3e2bed5ce5fe466395d2f5743d335b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/15/baeddbf3-eb06-4783-a66e-49338a7b618d.png?resizew=165)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5f1897a7e856b42f8cee0f286ad913d.png)
(2)若M为PA的中点,且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ed66431681da1db8f7cb0f40cd19201.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eb371bfd888c99be3ed4f95addec774.png)
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【推荐1】如图,多面体ABCEF中,
,
,D为BC的中点,四边形ADEF为矩形.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/121f0a38-c4b3-4eb4-a253-7c2803fe6f54.png?resizew=168)
(1)证明:
;
(2)若
,
,
,求异面直线CE与FD所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cbfc35fc915ac7d4dc017e60ccdecbe.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/121f0a38-c4b3-4eb4-a253-7c2803fe6f54.png?resizew=168)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31b2cc1d0bfd22c88286880b9da1f6f4.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fffa3d9c32da53b0ea0c338012ea20c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a702c324e0c76150540c3d32df802077.png)
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【推荐2】如图,
矩形
所在的平面,
,
分别是
,
的中点,
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/3/2cbcc87e-d7bd-46a3-b9a1-6dd51c8ada83.png?resizew=166)
(1)求证:
平面
;
(2)求证:
;
(3)若二面角
大小为45°,求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/3/2cbcc87e-d7bd-46a3-b9a1-6dd51c8ada83.png?resizew=166)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aab384f2520d76ed8fa01b31e09c1eea.png)
(3)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1de92fc2b7a7c63f4c1b0de2b1e0157.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89571b0ed015bc7533d44b73a74ba309.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
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【推荐3】. 如图,在三棱锥
中,
底面
,
,
,
,点
,
分别在棱
,
上,且
.
(Ⅰ)求证:
平面
;
(Ⅱ)当
为
的中点时,求
与平面
所成的角的大小;
(Ⅲ)是否存在点
使得二面角
为直二面角?并说明理由.
![](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/829f9180ddd9aa1a0ee0dc520f4e0b5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e075468e7fb0bf30229aec01a7205977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a3cc9cccfb4c260dac05f4ed57e8c10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95a078495ba47076ccaa28b46f765d80.png)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(Ⅱ)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(Ⅲ)是否存在点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ed479427d768bbf98c15141589109e1.png)
![](https://img.xkw.com/dksih/QBM/2012/1/11/1570685461790720/1570685467148288/STEM/742c35cd20464f0180fdc49875557a04.png?resizew=227)
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解题方法
【推荐1】如图,在四棱锥
中,底面
是正方形,
底面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/27/629b903f-85aa-4c50-8051-b688d7420cdb.png?resizew=143)
(1)求证:平面
平面
;
(2)若点
为
中点,求
(ⅰ)点
到直线
的距离;
(ⅱ)直线
与直线
所成角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf109530d399774ae2465fc324abffb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/27/629b903f-85aa-4c50-8051-b688d7420cdb.png?resizew=143)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04c222223dae9ef27d4c132534d9848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
(ⅰ)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c884b508394b3ab50734b584d9ec783c.png)
(ⅱ)直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c884b508394b3ab50734b584d9ec783c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
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【推荐2】如图,已知四边形
为菱形,且
,取
中点为E.现将四边形
沿
折起至
,使得
.
![](https://img.xkw.com/dksih/QBM/2021/3/29/2688264886362112/2689012383473664/STEM/dbe2f824718a4b8db5899a68e73999fe.png?resizew=554)
(1)求证:平面
平面
;
(2)试判断
上是否存在点F使
平面
,若存在,指出F的位置,并证明你的结论;若不存在,说明你的理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5b8b98b2f83279a49e94d9f48c5e6f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e1e4ea140260a790885868bc7a94f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30b29f99026a0ea8890fcd5ad58aebfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee58ba593d67bc5b59234f5beebf726.png)
![](https://img.xkw.com/dksih/QBM/2021/3/29/2688264886362112/2689012383473664/STEM/dbe2f824718a4b8db5899a68e73999fe.png?resizew=554)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e91e83004f1899951bf86c9a56a1f1cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30b29f99026a0ea8890fcd5ad58aebfb.png)
(2)试判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4add4f2d0dc3b8832581436af6aad41.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐3】已知四棱锥
,底面
为正方形,且
底面
,过
的平面与侧面
的交线为
,且满足
(
表示
的面积).
(1)证明:
平面
;
(2)当
时,二面角
的余弦值为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28ee2d2c33f73571cb9e3b96276f1acc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49a131604d5c482ec8edb88e00687277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f1c4ed7451103f0cbf14bb9ae219b43.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/18/24779f04-4ddc-4719-bb0f-da3ea8aab7bd.png?resizew=155)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa69a2247ad4d5231aa361349b12f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c66d99a6a8415ddad22bbed33b64cfb.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc4ba0f5fb4a61b67ce8f9984e6f7f49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/206695fadf6ab817ae8650f47fbf65d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f687ee88f27e8fe32de9d2435b3241f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次