Calculus III: Find a line perdendicular to XY-plane?
- Thread starter whig4life
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HallsofIvy
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Since we are given that one point on the line is (1, 0, -3), and x and y do not change, I would, personally, be inclined to look at (1, 0, 1), another point on that line.
whig4life, (when was the last time a whig held office?), here is another way to look at it: if the equation of a plane is Ax+ By+ Cz= D, then <A, B, C> is a vector perpendicular to the plane. And, of course, the equation of the xy-plane is just z= 0. That's where tkhunny got "(0, 0, 1)" although I would have written "<0, 0, 1>" to emphasize that this is a vector, not a point on the line.
whig4life, (when was the last time a whig held office?), here is another way to look at it: if the equation of a plane is Ax+ By+ Cz= D, then <A, B, C> is a vector perpendicular to the plane. And, of course, the equation of the xy-plane is just z= 0. That's where tkhunny got "(0, 0, 1)" although I would have written "<0, 0, 1>" to emphasize that this is a vector, not a point on the line.