己知A(1,-1),B(2,2),C(3,0)三点,求点D的坐标,使直线CD⊥AB,且CD//AD,
问题描述:
己知A(1,-1),B(2,2),C(3,0)三点,求点D的坐标,使直线CD⊥AB,且CD//AD,
答
设D(X,Y),等下向量AB*向量CD=0向量CD=m向量AD1*(x-3)+3*y=0;(x-3)*1=y*(x-1)
己知A(1,-1),B(2,2),C(3,0)三点,求点D的坐标,使直线CD⊥AB,且CD//AD,
设D(X,Y),等下向量AB*向量CD=0向量CD=m向量AD1*(x-3)+3*y=0;(x-3)*1=y*(x-1)