两个平面向量(交叉点,lineofintersection)求助.
x-y-2z=2
-x+y+z=3
(a)用叉乘解两个平面的交叉点的方向向量(directionofthelineofintersectionoftheplanes)
(b)用x=t,以x=p+tu的形式求两个平面的交叉点的向量方程.(Solvetheequationsimultaneoslytodeterminethelineofintersectionontheformx=p+tu)