题目

已知三棱锥中,平面,若,,与平面所成线面角的正弦值为,则三棱锥外接球的表面积为______. 答案:【答案】【解析】根据已知可得,可得三棱锥的外接球,即为以,,为长宽高的长方体的外接球,根据已知、、的长,代入长方体外接球直径(长方体对角线)公式,易得球半径,即可求出三棱锥外接球的表面积.解:平面,与平面所成线面角的正弦值为,,,根据勾股定理可得,在中,,,,则为直I wonder what will become of my son.________ endless homework, he also bears other leading loads such as revision and recitation(复习和背诵).A.WithB.Instead ofC.As well asD.Rather than
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