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20 17 Nanchang Ermoda Mathematics
Solution: (1) connected to AC, let AC∩EF=H,

Since ABCD is a square, AE=AF=4, and H is the midpoint of EF.

And ef < = ah, ef < = ch,

So there are A'H⊥EF, CH⊥EF,

∴EF⊥ Aircraft Company,

So plane A'HC⊥ plane ABCD, …(2 points)

If a' intersects with point A' so that A'O is perpendicular to HC and intersects with HC at point O, then A'O⊥ plane ABCD...(4 points)

The side length of square ABCD is 6, AE=AF=4,

Get: A'H=22, CH=42,

∴cos∠a′hc=8+32? 242×22×42= 12,

∴ho=a′h? cos∠A′HC = 2,A′O = 6,

∴ The volume of pentagonal cone A'-BCDFE V =13× (62-12× 4× 4 )× 6 = I have praised it and stepped on it. What is your evaluation of this answer? Put away comments//high quality or satisfaction or special types or recommended answers dottimewindow.iperformance & window.iperformance.mark ('c _ best',+newdate); Lawyer recommendation service: If your problem has not been solved, please describe your problem in detail and provide free professional consultation for other similar problems through Baidu Law Pro 2023-04-06 15. As shown in the figure, the sides of the square ABCD and AEFG are xy points E and G, respectively, on the AB side and above. For example, x+y = 29be = 22012-1,as shown in the figure, it is known that the side length of square ABCD is a, AC and BD intersect at E, FG∨AB intersect at E, and AD and BC intersect at F and G 22820/kloc respectively. BD is handed over to point E, FG∨AB is done after passing through point E, and AD and BC are handed over to points F and G respectively. Centered on point B, 322017-10-06 (2014? As shown in the figure, the side length of the square ABCD is 6, and the point E is on the side of AB and connected with ed. After passing through point D, the extension lines of FD⊥DE and BC intersect at 532011-10-24. As shown in the figure, square ABCD and EFCG are known, and points E, F and G are on line segments AC and G respectively. The side length of a square ABCD is 6412014-04-11. As shown in the figure, it is known that the side length of square ABCD is 1, and points E and F are on the sides of BC and CD respectively. If ∠ Eaf = 45。 AE length is half of the root. 5. Find the AF length112012-1-04 as shown in the figure. It is known that square ABCD and E, F, G, points E, F, G are on line segments AC, BC, G respectively. 2820 13-04- 17 As shown in the figure, it is known that the side length of square ABCD is 4, points E and F are on the sides of AB and BC respectively, AE = BF = 1, and CE and d F intersect with point 10. & gt recommended for you: F.context('cmsRight', [{'URL':'/d01373f082025aaf511aa256e9edab64034f1a07? x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto ',' contractId':'A24KA00562 ',},{ ' URL ':/s? word = % E6 % AC % A7 % E6 % B4 % B2 % E6 % 9D % AF & sa = searchpromo _ ozb _ zhidao _ tuijian ',' src ':'/3 BF 33 a 87 e 950352 AAF 5 df 4954 143 fbf2b 2 1 18 b6b? x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto ',' contractId ':' ',}]); The price of electric cars has dropped many times. Is the quality guaranteed? What impact will the "network toilet" have? Is Huaqiang North's second-hand mobile phone reliable? Why is the cost of cancer treatment getting higher and higher? I recommend f.context ('recbrand', [{"img": "\/86D6277F9E2F07083523F69DFB 24B 899A901F20d? x-BCE-process = image % 2f resize % 2Cm _ lfit % 2Cw _ 450% 2Ch _ 600% 2c limit _ 1% 2f quality % 2Cq _ 85% 2f format % 2Cf _ auto "," url":"/hm.js? 6859 ce 5a af 00 FB 00387 e 6434 E4 FCC 925 "; var s = document . getelementsbytagname(" script ")[0]; s.parentNode.insertBefore(hm,s); })(); window . TT = 1720082585;