Solution to Exercise 3.6.
Philosophy is the science which considers truth.
—Aristotle (384–322 BCE)

Exercise 3.6. Find two lines l[l₁ ,l₂, l₃] through the point (2, –3, 1).

 

Want .  Solving this equation, we obtain the following possible general forms:

  and  

Several possible examples are [1, 1, 1], [0, 1, 3], [1, 0, –2], etc.