MHB How to find the intersection point between two lines

AI Thread Summary
To find the intersection point between two lines defined by their parametric equations, different parameters must be used for each line. The equations provided are line 1: r = (3,1,-1) + s(1,2,3) and line 2: r = (2,5,0) + t(1,-1,1). The goal is to find values for s and t such that the resulting position vectors are equal. It is clarified that the parameters cannot be the same for both lines, as they represent distinct lines. Understanding this distinction is crucial for solving the intersection problem correctly.
Raerin
Messages
46
Reaction score
0
How to find the intersection point between two lines?

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + s(1,-1,1)
 
Last edited by a moderator:
Mathematics news on Phys.org
Raerin said:
line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + s(1,-1,1)

Hey Raerin! ;)

Let's use a different parameter in both of those line equations.

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + t(1,-1,1)

We're looking for an $s$ and a $t$, such that the resulting r is the same...Btw, perhaps you could also put your question inside your post instead of only as the title of the thread.
Your post looks a bit out of context now. :o
 
I like Serena said:
Hey Raerin! ;)

Let's use a different parameter in both of those line equations.

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + t(1,-1,1)

We're looking for an $s$ and a $t$, such that the resulting r is the same...Btw, perhaps you could also put your question inside your post instead of only as the title of the thread.
Your post looks a bit out of context now. :o
Haha! It Was a typo I see! I Was trying and trying, i Was like how can $$3+s= 2+s$$

Regards,
$$|\pi\rangle$$
 
I like Serena said:
Hey Raerin! ;)

Let's use a different parameter in both of those line equations.

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + t(1,-1,1)

We're looking for an $s$ and a $t$, such that the resulting r is the same...Btw, perhaps you could also put your question inside your post instead of only as the title of the thread.
Your post looks a bit out of context now. :o

------

So it's not possible for both parameters to be s? Then there's a mistake in the question. I guess I don't need help anymore. Thanks!
 
Raerin said:
------

So it's not possible for both parameters to be s? Then there's a mistake in the question. I guess I don't need help anymore. Thanks!

It's not really a mistake in the question.
The general form of a line equation is $\vec r = \vec a + s \vec d$.
However, when you intersect 2 different lines with such an equation, you have to realize that the parameters $s$ in those 2 line equations are distinct.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Is it possible to arrange six pencils such that each one touches the other five? If so, how? This is an adaption of a Martin Gardner puzzle only I changed it from cigarettes to pencils and left out the clues because PF folks don’t need clues. From the book “My Best Mathematical and Logic Puzzles”. Dover, 1994.
Thread 'Imaginary Pythagoras'
I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...
Back
Top