赚现金
如图,在直三棱柱ABC—A1B1C1,AB=AC=1,∠BAC=90°,连结A1B与∠A1BC=60°.(Ⅰ)求证:AC⊥A1B;(Ⅱ)设D是BB1的中点,求三棱锥D-A1BC1的体积.
试题篮