答案如图所示,p为三角形abc所在平面外一点,pa,pb,pc两两垂直,ph垂直平面abc于h.求证ah垂直bc

答案如图所示,p为三角形abc所在平面外一点,pa,pb,pc两两垂直,ph垂直平面abc于h.求证ah垂直bc

AP⊥BP AP⊥PC==>AP⊥PBC==>AP⊥BC
PH⊥ABC==>PH⊥BC
PH⊥BC,AP⊥BC==>BC⊥APH==>BC⊥AH