如图,在直三棱柱ABC-A
1B
1C
1中,∠ACB=90°,E,F,G分别是AA
1,AC,BB
1的中点,且CG⊥C
1G.
(Ⅰ)求证:CG∥平面BEF;
(Ⅱ)求证:CG⊥平面A
1C
1G.
考点分析:
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