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发表于:2018-07-28
Hoptothatlilypadinthesky,oldfriend.AgreenfrogsitsatopalargelilypadinthewatersofAtchafalayaDelta.WhenCharleysawWandahejumpedontoalilypad."Hi,"hecried.Hewasahandsomeprinc...
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发表于:2019-09-13
问题详情:如图所示,已知AD∥BC,∠ABC=90°,AB=8,AD=3,BC=4,点P为AB边上一动点,若△PAD与△PBC相似,则AP= .【回答】4解析由AD∥BC,∠ABC=90°,易得∠PAD=∠PBC=90°,又由AB=8,AD=3,BC=4,设AP的长为x,则BP...
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发表于:2022-04-18
问题详情:如图,在四棱锥P﹣ABCD中,底面ABCD是边长为2的正方形,侧面PAD⊥底面ABCD,且PA=PD=AD,E、F分别为PC、BD的中点.(Ⅰ)求*:EF∥平面PAD;(Ⅱ)求*:面PAB⊥平面PDC;(Ⅲ)在线段AB上是否存在点G,使得二面角C...
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发表于:2024-02-23
1、scratchpadmemory2、scratchpadregister3、DoyouhaveascratchpadIcanwriteon?4、Theinventionrelatestoamulticolorscratchpad,acollatingmethodthereofandamulticolorscratchpadco...
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发表于:2021-08-28
问题详情:如图,在四棱锥中,O为AC与BD的交点,平面PAD,是正三角形,,. (1)若点E为棱PA上靠A近的三等分点,*:直线平面PBC; (2)求*:平面平面PDC. 【回答】*: (1)因为,,所以.………...
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发表于:2024-02-10
1、Modernbrakesystemscanincorporatepressuresensorswhichdeterminebrakecylinderpressureorevenbrakepadpressure.2、Temperature-risinglawsofdrumbrakepadfortruckonlongdowngrade...
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发表于:2017-07-17
Fixedthattheplayercharacterwouldmoveincorrectlyonthelandingpadifthepadwasflooded.TheritziesthotelinMuscatoffersahelicopterlandingpadoutback.Ifthethoughtofpublictoiletwate...
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发表于:2018-03-26
Startbynotbuyingyourselfasketchpad.Comparedtothephonologicalloopandthevisuospatialsketchpad,thecentralexecutivemayhaveakeyroleinchildren'sarithmeticcognition.Comparedtot...
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发表于:2018-09-30
Scrubeachopticalsurfacewithagauzepadsoakedinacetone.Ihadtopayrushshippingformybirthkit—allthesterilizedgauzepads,alcoholswabs,glovesandgoopthemidwifeneedsatthebirth.Firs...
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发表于:2022-03-24
telephonenumBerswrittenonapadShewroteonapadofpaper.NexttoPaulsen,NimGoldmandoodledthoughtfullyonapad.Heputonapadofgauzeandastripofadhesivetapeoverthewound.Mobilehomeortra...
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发表于:2020-09-14
问题详情:如图,四棱锥P-ABCD中,侧面PAD是边长为2的等边三角形且垂直于底,是的中点.(1)*:直线平面;(2)点在棱上,且直线与底面所成角为,求二面角的余弦值.【回答】(1)见解析;(2)【详解】试题分析:(1)取的中点,连...
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发表于:2017-07-07
fixingofshoulderpadThepadisimpregnatedwithinsecticide.Neverpadoutyouressaywithirrelevantdetails.Startbynotbuyingyourselfasketchpad.Sheseesthestamppadonmysweater.Amongthos...
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发表于:2018-08-17
Avoidingputtingyourelbowonhardsurfacesmayhelp,orwearinganelbowpadovertheulnarnerveand"funnybone"mayhelp.MayIborrowyourkneepadsandelbowpads?Ofcourse,besuretheyhaveonprot...
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发表于:2020-04-30
问题详情: 如图,在四棱锥P-ABCD中,底面ABCD为平行四边形,己知AP=AC=AB=2,∠PAD=∠DAC=60°.(1)求*:AD丄PC;(2)若平面PAD丄平面ABCD,求二面角C-PD-A的余弦值.【回答】知识点:点直线平面之间的...
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发表于:2020-10-19
问题详情:小明喜欢利用pad听歌,根据声音的(选填“音调”、“响度”或“音*”)就判断出是哪位歌手;音量太大会使耳膜受损,说明声能传递 (“信息”或“能量”),为此需要减小声音的 (“音调”、“...
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发表于:2021-02-04
问题详情:如图,四棱锥P-ABCD中,底面ABCD为矩形,侧面PAD为正三角形,且平面PAD⊥平面ABCD,E为PD中点,AD=2.(1)求*:平面AEC⊥平面PCD;(2)若二面角A-PC-E的平面角大小θ满足,求四棱锥P-ABCD的体积. ...
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发表于:2021-02-27
问题详情:如图,四棱锥P-ABCD中,侧面PAD为等边三角形且垂直于底面ABCD,AB=BC=AD,∠BAD=∠ABC=90°。(1) *:直线BC∥平面PAD;(2) 若△PAD面积为2,求四棱锥P-ABCD的体积。【...
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发表于:2020-08-11
问题详情:在四棱锥△PAD为正三角形,且平面PAD⊥平面ABCD.(1)求二面角P-EC-D的余弦值;(2)线段PC上是否存在一点M,使得异面直线DM和PE所成的角的余弦值为若存在,指出点M的位置;若不存在,请说明...
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发表于:2018-06-21
LateMondayafternoon,readingtheobscureandintricatemarkings,theyidentifiedalaunchingpad.Thecenterpiecewasanornatemodelrocketonagreenfaunalaunchingpad.UponreturningtoEngland...
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发表于:2020-05-16
问题详情:在四棱锥P-ABCD中,AD∥BC,,G是PB的中点,△PAD是等边三角形,平面PAD⊥平面ABCD.(Ⅰ)求*:CD⊥平面GAC;(Ⅱ)求二面角P-AG-C的正弦值.【回答】知识点:点直线平面之间的位置题型:解答题...
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发表于:2023-12-28
1、Hewrotedownatelephonenumberonamemopad.2、Inthedream,hereachedfortheblueballpointpeninhisbreastpockettojotsomethingdownonhismemopad.3、Thephonehasanintegratedquicknotef...
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发表于:2016-10-17
Thereportersreportedthatthelaunchpadwasonfireafterthelaunch.Themilitaryhasnotbeenabletodeterminetheexactlocationofthelaunchpad.Therocketexplodedonthelaunchpad,burningaliv...
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发表于:2018-05-13
Asanitarybreastpadrelatestothetechnicalfieldofwomanhealth-carearticles,inparticulartoasanitarypadusedforkeepingthecircumferenceandclothesdryforwomeninlactationperiod.Fore...
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发表于:2022-04-19
问题详情:如图,四棱锥P-ABCD中,侧面PAD为等比三角形且垂直于底面ABCD,E是PD的中点.(1)*:直线平面PAB(2)点M在棱PC上,且直线BM与底面ABCD所成锐角为,求二面角M-AB-D的余弦值 【回答】【解析】(1)令...
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发表于:2019-10-25
问题详情:如图,在四棱锥P-ABCD中,侧面PAD为正三角形,底面ABCD为正方形,侧面PAD⊥底面ABCD,M为底面ABCD内的一个动点,且满足MP=MC,则点M在正方形ABCD内的轨迹为( ) ...