x=(-2t^2-1,t^2+3)
y=(-1/k-2/t,-2/k+1/t)
x平行于y
(-2t^2-1)(-2/k+1/t)=(t^2+3)(-1/k-2/t)
4t^2/k-2t+2/k-1/t=-t^2/k-2t-3/k-6/t
5t^2/k+5/k+5/t=0
k,t 为正实数,
5t^2/k+5/k+5/t=0无解
不存在
x=(-2t^2-1,t^2+3)
y=(-1/k-2/t,-2/k+1/t)
x平行于y
(-2t^2-1)(-2/k+1/t)=(t^2+3)(-1/k-2/t)
4t^2/k-2t+2/k-1/t=-t^2/k-2t-3/k-6/t
5t^2/k+5/k+5/t=0
k,t 为正实数,
5t^2/k+5/k+5/t=0无解
不存在