Finding the scalar equation of a plane

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Homework Statement


Find the equation of the plane that goes through points P, Q and R. P = (3, -1, 2), Q = (8, 2, 4) and R = (-1, -2, -3)

Homework Equations


Eq of plane
0 = a(x - x0) + b(y - y0) + c(z - z0)

The Attempt at a Solution


In order to find vector normal to the plane, my teacher took the cross product of PQ X PR. Would I still get the correct normal vector if I take the cross product of PQ X QR? Finally, when I plug in the numbers to the equation in "

Homework Equations

", does it matter which point I choose (P, Q or R) for x0, y0, or z0? Thank you.
 
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Calpalned said:

Homework Statement


Find the equation of the plane that goes through points P, Q and R. P = (3, -1, 2), Q = (8, 2, 4) and R = (-1, -2, -3)

Homework Equations


Eq of plane
0 = a(x - x0) + b(y - y0) + c(z - z0)

The Attempt at a Solution


In order to find vector normal to the plane, my teacher took the cross product of PQ X PR. Would I still get the correct normal vector if I take the cross product of PQ X QR? Finally, when I plug in the numbers to the equation in "

Homework Equations

", does it matter which point I choose (P, Q or R) for x0, y0, or z0? Thank you.
Yes, you can use PQ×QR or, for that matter, PR×QR . Each gives a vector which is normal to the plane.

No, it doesn't matter which point you use. Try more than one and compare results.
 
SammyS said:
Yes, you can use PQ×QR or, for that matter, PR×QR . Each gives a vector which is normal to the plane.

No, it doesn't matter which point you use. Try more than one and compare results.

Thank you
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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