在三棱柱ABC—A1B1C1中,四边形A1ABB1是菱形,四边形BCC1B1是矩形,C1B1⊥AB ,若C1B1垂直AB,若C1B1=3,AB=4,角ABB1=60度,求AC1与平面BCC1所成角度
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å¨ç´è§ä¸è§å½¢AMC1ä¸ï¼tanAC1M=AM/C1M=2â3/â13=0.9608ï¼â´â AC1M=43.85°约43°51â²ã