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Answers to the Second Mathematical Model in Changning District
Solution: (1) Take d as the coordinate origin, and establish a spatial rectangular coordinate system. D (0,0,0),A (a,0,0),B(a,A,0),C (0,A,0)。 Let DE=t,

Then e (0 0,0, t)(2 points)

AC=(? A, a, 0), BE=(-a, -a, t), (4 points)

∵AC? BE=a2? A2+0=0,∴ AC ⊥ Be。 (6 points)

(2) Let a normal vector of the plane ADE be n 1=(0 = (0, 1, 0). (7 points)

Let a normal vector of plane ACE be n2=(x, y, z), AE=(-a, 0, t),

Damn it, AE I 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 through Baidu Law Professional Edition. Other similar questions 20 12-06-02. As shown in the figure, in the quadrangular cone S-ABCD, the ABCD at the bottom of SD⊥ is rectangular, SD=AD=√2AB, and E is the midpoint of AB. 122011-07-0725. As shown in the figure, in the quadrangular pyramid S-ABCD, the bottom ABCD of SB is rectangular, and the point E is SB.172013-07-/kloc. Point M is the midpoint of an⊥sc SD, and it intersects SC at point N.162012-01-kloc-0/9. As shown in the following figure, the bottom surface of the quadrangular cone S-ABCD is rectangular, and the bottom surfaces of SA⊥ ABCD, E, F E and F are SD and SC respectively. Verification: (1)BC⊥ aircraft sab (2) ef ⊥ SD102014-12-03 (2014? As shown in the figure, let S-ABCD be a pyramid with a height of 3, the bottom ABCD be a square with a side length of 2, and the projection of the vertex s on the bottom is 220 13-08-27. As shown in the figure, in the quadrangular cone S-ABCD, the bottom ABCD is a square, SA⊥ bottom ABCD, SA=AB, and point M is the midpoint of SD. And cross SC at point N220 13-07-07 as shown in the figure. In the quadrangular pyramid S-ABCD, the bottom ABCD is a diamond, s a⊥ bottom ABCD, m is the midpoint of S A, and n is the midpoint of CD. More similar questions? & 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 = 17200695 17;