1.已知三角形ABC的内角A,B及其对应边a,b满足a+b=acotA+bcotB,求内角C2.如图,已知四棱锥S-ABCD中,SD垂直底面ABCD,AB平行DC,AD垂直DC,AB=AD=1,DC=SD=2,E为棱SB上一点,平面EDC垂直平面SBC,①求证SE=2EB②求二面角A-D
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/29 09:06:26
![1.已知三角形ABC的内角A,B及其对应边a,b满足a+b=acotA+bcotB,求内角C2.如图,已知四棱锥S-ABCD中,SD垂直底面ABCD,AB平行DC,AD垂直DC,AB=AD=1,DC=SD=2,E为棱SB上一点,平面EDC垂直平面SBC,①求证SE=2EB②求二面角A-D](/uploads/image/z/1742731-43-1.jpg?t=1.%E5%B7%B2%E7%9F%A5%E4%B8%89%E8%A7%92%E5%BD%A2ABC%E7%9A%84%E5%86%85%E8%A7%92A%2CB%E5%8F%8A%E5%85%B6%E5%AF%B9%E5%BA%94%E8%BE%B9a%2Cb%E6%BB%A1%E8%B6%B3a%2Bb%3DacotA%2BbcotB%2C%E6%B1%82%E5%86%85%E8%A7%92C2.%E5%A6%82%E5%9B%BE%2C%E5%B7%B2%E7%9F%A5%E5%9B%9B%E6%A3%B1%E9%94%A5S-ABCD%E4%B8%AD%2CSD%E5%9E%82%E7%9B%B4%E5%BA%95%E9%9D%A2ABCD%2CAB%E5%B9%B3%E8%A1%8CDC%2CAD%E5%9E%82%E7%9B%B4DC%2CAB%3DAD%3D1%2CDC%3DSD%3D2%2CE%E4%B8%BA%E6%A3%B1SB%E4%B8%8A%E4%B8%80%E7%82%B9%2C%E5%B9%B3%E9%9D%A2EDC%E5%9E%82%E7%9B%B4%E5%B9%B3%E9%9D%A2SBC%2C%E2%91%A0%E6%B1%82%E8%AF%81SE%3D2EB%E2%91%A1%E6%B1%82%E4%BA%8C%E9%9D%A2%E8%A7%92A-D)
xU]O"g+d+AevÀn/i4 B
qW*hW֏KZWD"vޙʿݛhҤ{ssهYFtK45 fPaMJ5V]|>=QV3c>>%ʬN81Qދ&PE9QhQm/iH3jox>aOPc."s(xR#1bQ1yj5 Y\2j3FM&AXq)J,n&2fqL1n+O}9"AФtX _g(h\>LsѭfϵgYOvWO
c|i:eޅzQ@TYrͭ3;>Z(f'_
WINsCHoN1wzV8$iFe5.6s{䶹A6/NF V2ݙ2ژ`k(?%$JOη(`^iSl._0l_+u