如图,在长方体ABCD﹣A1B1C1D1中AA1=AD=1,E为CD中点.
求证:B1E⊥AD1
负责调节人体体温和水盐平衡的神经中枢位于( )
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已知命题P:∀x∈R,cosx≤1,则( )
若集合M={x|-2<x<3},N={y|y=x2+1,x∈R},则集合M∩N=( )