[填空题]
Consider the vectorsj 4uia:eog9- o.cr m-oww k q,l-jel7+m.rzl4 $\mathbf{a}=2 \mathbf{i}+\mathbf{j}-4 \mathbf{k}$ and $ \mathbf{b}=\mathbf{i}-2 \mathbf{j}+5 \mathbf{k}$ .
1. Find $ \mathbf{a} \times \mathbf{b}$ .
2. Hence find the Cartesian equation of the plane containing the vectors $\mathbf{a}$ and $\mathbf{b}$ and passing through the point P(2,-1,0) . -3x-14y-5x=
