Finding the Vector Eqn of a Line

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To find the vector equation of a line passing through the point P(2, -1, 3) and perpendicular to the plane defined by 3x - 2y - z = 0, the direction vector can be derived from the normal vector of the plane, which is 3i - 2j - k. The equation of the line can then be expressed as Line(x) = P + td, where P is the point and d is the direction vector. The normal vector of the plane serves as the direction vector for the line. This approach effectively provides the necessary components to formulate the vector equation. Understanding the relationship between the plane's normal vector and the line's direction is crucial in solving this problem.
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Homework Statement



Find the Vector eqn of a line which passes through P(2, -1, 3) and is perpendicular to the plane 3x -2y -z =0.

Homework Equations



Line(x) = P + td where d is a direction vector

The Attempt at a Solution



My main problem here is trying to find the direction vector for the line. I have really no idea how to find that. Any help is greatly appreciated :)
 
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I think I figured it out...I can use the normal vector of the plane as my direction vector.
 
Yes, that's exactly right. And that, of course, is just 3i- 2j- k.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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