Plane ABD⊥ plane BCD, plane ABD∩ plane BCD=BD. ..

∴CD⊥ plane Abd...(3 points)

? AB again? Aircraft ABD, ∴ CD ⊥ AB...(4 points)

(2) Solution: Take point D as the origin, the straight line of BD as the X axis, and the straight line of DC as the Y axis, and establish a spatial rectangular coordinate system, as shown in the figure. A (1, 0, 1), B (2 2,0,0), C (0 0,2,0) and D(0) are known.

∴CD=(0？ 2，0)，AD=(？ 1,0,? 1) ...(6 points)

Let the normal vector of plane ACD be n = (x, y, z), then CD⊥n, AD⊥n, ∴ y = 0x+z = 0.

Let x= 1, and a normal vector of the plane ACD is n = (1, 0,? 1),

∴ distance from point m to plane ACD = | n? MC || MC | = 22...(8 points)

(Ⅲ) Solution: Let there be a point n on the BC line, so that the angle between an and plane ACD is 60 ... (9 points).

Let bn = λ BC,? 0 < λ < 1, then N(2-2λ, 2λ, 0),

∴AN=( 1？ 2λ,2λ,? 1),

Normal vector n = (1, 0,? 1) and the angle between the straight line an and the plane ACD is 60,

∴sin60 = | Ann? n||AN|？ | n | = I have already praised stepping on it. What's your comment on 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- 126. As shown in the figure, in the right-angled trapezoidal ABCD, AB =3CD, ABC =30, BC =4, and the trapezoidal ABCD around AD is 2011-0/0. As shown in the figure, DC ‖ AB, ∠ ADC = 90, AB = 3A, CD = 2A, and AD = 265438+ in right-angled trapezoidal ABCD. Guangdong) is known: As shown in the figure, in the right-angled trapezoid ABCD, ab∑CD, AD⊥AB, the vertical foot is A, and the semi-circular O-tangent AD with the diameter of waist BC is 5201-0/-kloc-0/-304, as shown in Figure 8, in the right-angled trapezoid ABCD, AB \. Tan ∠ AB ⊥ BC = 2.42017-10-30 As shown in the figure, AB=2CD, AB ∠ DC, ab∑DC, ∠ AD=4 60 in a right-angled trapezoid. & 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 = 1720 100990；