解题方法
1 . 如图,在四棱锥
中,底面
是矩形,面
底面
,且
是边长为
的等边三角形,
,
在
上,且
∥面BDM.
(1)求直线PC与平面BDM所成角的正弦值;
(2)求平面BDM与平面PAD所成锐二面角的大小.
![](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/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e1b638760d907efe836500581da1596.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
(1)求直线PC与平面BDM所成角的正弦值;
(2)求平面BDM与平面PAD所成锐二面角的大小.
![](https://img.xkw.com/dksih/QBM/2017/5/12/1685224172118016/1686650427031552/STEM/44c5d52ee0e14ac1bea2874993e4bd8c.png?resizew=254)
您最近一年使用:0次
2017-05-14更新
|
681次组卷
|
2卷引用:江苏省盐城市2017届高三第三次模拟考试数学(理)试题
解题方法
2 . 如图,在几何体
中,底面
为矩形,
,
.点
在棱
上,平面
与棱
交于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/14/dc620218-b7ae-4a5f-8bff-99debc5987d2.png?resizew=220)
(1)求证:
;
(2)求证:平面
平面
;
(3)若
,
,
,平面
平面
,求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/975192d4ea9872ac2bd1f37a8c984548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a417b3d5f4a7eb3b035cf6f61002fdca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/735056c174e8dd7906257a2a50a962a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ddb7c2ca1b6bee86cb24fed02e40da2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2319a01218514917e446dfc807a625ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/14/dc620218-b7ae-4a5f-8bff-99debc5987d2.png?resizew=220)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bf54fe93a8c77d1443bfb3f35d530b.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/feece30451c64dc568ace836b39e5876.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30b7f93bcf621d7a3abd80bb3e3d64a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4d3d4307b9f64d8c99f864941f37874.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad34aa4ab53b0f85f6f02d07968eeeec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64899adb2cc8913ed7d511eade821422.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19fccb51073a0dbb6c7c36c3c375e6d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c7712b52f01080354c99159c62b5a61.png)
您最近一年使用:0次
2017-05-12更新
|
608次组卷
|
2卷引用:北京市西城区2017届高三二模数学理科试题
解题方法
3 . 如图,在直三棱柱
中,
,
,
为
上的点,
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/27/2119522c-4957-4f6b-bfa4-8572613fc22f.png?resizew=207)
(1)求证:
平面
;
(2)若
,且
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea6ff6a807f5639faac835012b3728c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5df66362082c13c887223771b92a1f6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/547a4b438e2e6687c7cd55ea08bbaae2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/27/2119522c-4957-4f6b-bfa4-8572613fc22f.png?resizew=207)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e53b212640dadf751ef7f65a78a209.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a02cfc067dc5299ebb16f6378f90ff5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1157a6da4c4028b7216f7c9740d63aee.png)
您最近一年使用:0次
2017-05-04更新
|
516次组卷
|
3卷引用:四川省遂宁市2017届高三三诊考试数学(文)试题2
解题方法
4 . 如图,在直三棱柱
中,
是线段
上一点.
点.
![](https://img.xkw.com/dksih/QBM/2017/5/8/1682702595219456/1683376827490304/STEM/1fec0b76ad864181941e2fd27c1312ae.png?resizew=134)
(1)确定
的位置,使得平面
平面
;
(2)若
平面
,设二面角
的大小为
,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1055a1a2f7d49f6ac6a5b696cdf9742d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
点.
![](https://img.xkw.com/dksih/QBM/2017/5/8/1682702595219456/1683376827490304/STEM/1fec0b76ad864181941e2fd27c1312ae.png?resizew=134)
(1)确定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f96e23f7b5d3b1dcac47c19fd6da8860.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caf9f23573559a43588ef985569d012d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4557a368725226f2c8ea2efb7d30e478.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f62fd0b510920be6bc60d170c3ff3da3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0ba51c39cd2a199c701a7625e6c94eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e93c92189deee440057d5aadedd070be.png)
您最近一年使用:0次
2017-05-03更新
|
142次组卷
|
2卷引用:山西省晋中市榆社中学2016-2017学年高二下学期期中考试理科数学试题
解题方法
5 . 如图,四棱锥
中,底面
是矩形,平面
底面
,且
是边长为
的等边三角形,
在
上,且
∥面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/12/889f8e8f-91fa-4e32-92a7-1101f25ac083.png?resizew=179)
(1)求证:
是
的中点;
(2)求多面体
的体积.
![](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/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44876626adf7688cdef5ac9de739a965.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af29254fe60a392c249c5791279e9c8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/12/889f8e8f-91fa-4e32-92a7-1101f25ac083.png?resizew=179)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
(2)求多面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e62d57ea0f1e0f8333d4f6adb1c0ca9.png)
您最近一年使用:0次
解题方法
6 . 以
为直径的圆
经过
、
两点,延长
、
交于
点,将
沿线段
折起,使
点在底面
的射影恰好为
的中点
.若
,
,线段
、
的中点分别为
.
![](https://img.xkw.com/dksih/QBM/2017/3/25/1651663230844928/1652300433588224/STEM/38ca8074bc7f44e59e69825a12f8d745.png?resizew=164)
![](https://img.xkw.com/dksih/QBM/2017/3/25/1651663230844928/1652300433588224/STEM/a659fa0f2c6141988ac92042b9e011b8.png?resizew=185)
(1)判断四点
是否共面,并说明理由;
(2)求四棱锥
的体积.
![](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/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d822262ff00915910e5b87d81ad1ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2205cffebf8c4d5f81d15ed7b85c8936.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/714cc3707bba3bfdb56e251999be8592.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/86ff08d656803ee89aa3c6ed4a952648.png)
![](https://img.xkw.com/dksih/QBM/2017/3/25/1651663230844928/1652300433588224/STEM/38ca8074bc7f44e59e69825a12f8d745.png?resizew=164)
![](https://img.xkw.com/dksih/QBM/2017/3/25/1651663230844928/1652300433588224/STEM/a659fa0f2c6141988ac92042b9e011b8.png?resizew=185)
(1)判断四点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/321f077315ab7f569707347846ce7e4f.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb3ca447f79222bc8da4c7a242f42010.png)
您最近一年使用:0次
名校
解题方法
7 . 如图,在以
为顶点的五面体中,面
为矩形,
,且二面角
与二面角
都等于
.
![](https://img.xkw.com/dksih/QBM/2017/3/20/1647873467482112/1649132632612864/STEM/25bde063f0a84f03a6efa6597eef023c.png?resizew=253)
(Ⅰ)证明:平面
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b56b726b78d55f4e6943ce5c19fbeac2.png)
(Ⅱ)求证:四边形
为等腰梯形;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5489a5fbd1f73b36ee27b618747e0dc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b54a965aa682d6d2aa484a43d4941c91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12d7204dead053ff861e083c587a41b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc0d363974899c982cfa4b11bcc60277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/494ffe7fe98b7d198bdd5d707cf6b66f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96d9a623ca927a1a0cfd038663c4fd48.png)
![](https://img.xkw.com/dksih/QBM/2017/3/20/1647873467482112/1649132632612864/STEM/25bde063f0a84f03a6efa6597eef023c.png?resizew=253)
(Ⅰ)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/097f637e4a68e179658abd07c6eaa709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b56b726b78d55f4e6943ce5c19fbeac2.png)
(Ⅱ)求证:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b56b726b78d55f4e6943ce5c19fbeac2.png)
您最近一年使用:0次
解题方法
8 . 如图,在斜三棱柱
中,侧面
是菱形,
与
交于点O,E是棱
上一点,且
平面
.
![](https://img.xkw.com/dksih/QBM/2017/3/15/1644570517929984/1649114046242816/STEM/1698d9e74e79470bb6f2ac9988a94c94.png?resizew=212)
(1)求证:E是
的中点;
(2)若
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af142a6050b54e8b5777a085d4597481.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://img.xkw.com/dksih/QBM/2017/3/15/1644570517929984/1649114046242816/STEM/1698d9e74e79470bb6f2ac9988a94c94.png?resizew=212)
(1)求证:E是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1515a445310d259a080d02e16c2e58e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/619174cab53737ab3547ec3970f42575.png)
您最近一年使用:0次
2017-03-22更新
|
587次组卷
|
2卷引用:2016-2017学年江苏苏锡常镇四市高三教学情况调研(一)数学试卷
解题方法
9 . 在四棱锥
中,
平面
,底面
为矩形,点
分别为棱![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6a6c73460fc85548ceaffabd160a780.png)
的中点,
为线段
的中点,且
为
上一点,且
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6261790c66cc71ee3898afabad0c09f4.png)
![](https://img.xkw.com/dksih/QBM/2017/2/16/1625388693053440/1633072752984064/STEM/3d9b6889dd2443cbb6e84c0dd7df3010.png?resizew=199)
(1)确定
的位置,并求线段
的长;
(2)平面
与
交于点
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84a8530f48e33908c770d451448fbb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6a6c73460fc85548ceaffabd160a780.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c4cd264c97c1f261229925cc5a6761.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b46c607b3deac746c0ef3389ad8f65c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05045a3caf35e82d14f1792ba0db8c0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fddbb7f29e8672f34941fe70b0a1e45f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4b05c07fd4285e0b4896771e08d96fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6261790c66cc71ee3898afabad0c09f4.png)
![](https://img.xkw.com/dksih/QBM/2017/2/16/1625388693053440/1633072752984064/STEM/3d9b6889dd2443cbb6e84c0dd7df3010.png?resizew=199)
(1)确定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff4a63d14654c66cc71bf26293d698ec.png)
(2)平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6261790c66cc71ee3898afabad0c09f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/929ca3cae393e9f27f30b8b9461f854c.png)
您最近一年使用:0次
解题方法
10 . 如图,已知四边形
是平行四边形,点
是平面
外一点,
是
的中点,在
上取一点
,过
和
作平面交平面
于
.
(1)求证:
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bc46688d8723cf2003fc25890265200.png)
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15a424b50eaeafa6f302ffd95476cb86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bc46688d8723cf2003fc25890265200.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/011abe509df00fe9410ab08b585ad7db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bc46688d8723cf2003fc25890265200.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8adf16ba03aeaab7e159522bee841377.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/24/d9c9e451-d0e4-48e6-8aa1-3ef79d897047.png?resizew=176)
您最近一年使用:0次