Are the given lines in R^3 concurrent or parallel?

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To determine if three planes intersect at a single point, one can analyze the normal vectors of the planes to check for linear independence. For the given lines L1, L2, and L3 in R^3, it is essential to first assess if any lines are parallel by examining their direction vectors. If any lines are parallel, they cannot be concurrent. For the intersection of L1 and L2, the point can be found by solving their parametric equations. Finally, the distance between L3 and L2 can be calculated using the information from their concurrency analysis.
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Homework Statement



Ok I have a bunch of questions, please bare with me and i'd appreciate it VERY much if you could help me with these!

1. Assume that you are given the equations of three planes. Without solving the system, describe a "test" with rationale, that you could use to determine whether or not the planes intersect at a single point.

2. Given the equations of three lines in R^3

L1 = (1,4,1) + t(3,3,-2)
L2 = (-3,-5,8) + r(5,0,1)
L3 = (3,-5,8) + s(-5,0,-1)

a) Can all three lines be concurrent (i.e interesect at one point)? Algebraic solution not required

b) Determine the point of intersection of L1 and L2

c) Use information of part a) to help in determining the distance between L3 and L2


End questions.


I'd appreciate it a lot if someone can help me... :(

Homework Equations



I'm not sure, I got these questions on a whim and my textbook doesn't offer much help other than simple formulas.

The Attempt at a Solution



I'm really unsure how to approach these questions.. I got them on a whim and I haven't faced this unit of calculus before..
 
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Can you make more of an attempt at the questions? It's better you show us what you think instead of us just telling you the answers.

I'll get you started.

For 2a) a good place to start would be to determine whether any of the lines are parallel or not. After all, if they are parallel to one another, surely they won't intersect!

HINT: Look at the direction vectors of the each line.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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