MHB Parametric Eqs: Find Line & Plane, Find Triangle Area

AI Thread Summary
The discussion focuses on deriving parametric equations for a line through points P and Q, and the equation of a plane through points P, Q, and R, without using known formulas. Participants emphasize the importance of understanding the underlying concepts rather than relying on formulas. The area of the triangle formed by the points P, Q, and R is calculated using the cross product method. Concerns are raised about the original poster's lack of effort in solving the problems independently, suggesting a need for better comprehension of the instructions. The conversation highlights the balance between providing help and encouraging self-sufficiency in problem-solving.
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Let P (1, 2, 3), Q (2, 3, 1), and R (3, 1, 2).
(a) Derive the parametric equations for the line that passes through P and Q without resorting
to the known formula.
(b) Derive the equation of the plane that passes through the points P, Q, and R without
resorting to the known formula.
(c) Find the area of the triangle with vertices P, Q, and R.
 
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skeeter said:
(a) initial point + (direction vector) times t

(b) Calculus III - Equations of Planes (lamar.edu)

(c) area = $\dfrac{1}{2} |\vec{PQ} \times \vec{PR} |$

And I would hope that the OP would have found $\displaystyle \vec{PQ} \times \vec{PR}$ in part b) :P
 
Prove It said:
And I would hope that the OP would have found $\displaystyle \vec{PQ} \times \vec{PR}$ in part b) :p

seeing how the OP has posted the same problems on two other math help sites, I would hope so, also
 
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It is not clear to me whether the OP's problem is with math or with reading English. He does not appear to have read, or understood, the instructions for this board. He has posted 8 or more threads without showing any attempt to solve them himself. I feel that I, at least, have already done too much.
 
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