图上有个东东我没画,就是这个平面的法向量。
One thing that's on this picture that I haven't drawn down is the normal vector to the plane.
重点：直线的方向向量与平面的法向量的应用。
Key points: application of the direction vector of a line and the normal vector of a plane.
我们已经知道，如何根据系数找到这个平面的法向量。
And, we know how to find a normal vector to this plane just by looking at the coefficients.
应用推荐