Chứng minh BC ⊥ (AID)

$$\begin{gathered} \mathrm{Cho} \mathrm{tứ} \mathrm{diện} \mathrm{ABCD} \mathrm{có} \mathrm{DA} \perp \left(\mathrm{DBC}\right) \mathrm{và} \mathrm{tam} \mathrm{giác} \mathrm{ABC} \mathrm{vuông} \mathrm{tại} \mathrm{A}. \mathrm{Kẻ} \mathrm{DI} \perp \mathrm{BC}. \\ 1, \mathrm{Chứng} \mathrm{minh} \mathrm{BC} \perp \left(\mathrm{AID}\right). \\ 2,\mathrm{Kẻ} \mathrm{DH} \perp \mathrm{AI} \mathrm{Chứng} \mathrm{minh} \mathrm{DH} \perp \left(\mathrm{ABC}\right). \end{gathered}$$