Interval notation and specifying units (v vs. t graph)

AI Thread Summary
The discussion revolves around how to express time intervals in interval notation for a physics problem involving a particle's movement. Participants are uncertain whether to include units (seconds) in the interval notation. The suggested answers for the intervals are (45, 87.5) for one question and [0, 45) U (87.5, 100] for another. The intervals indicate when the particle is moving to the right, specifically between 0 to 45 seconds and 87.5 to 100 seconds, while it moves left between 45 and 87.5 seconds. The conversation highlights the lack of guidance from the professor and textbook on this unique question.
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Homework Statement



#5 and #6 of the attached pdf on page 5 (graph on page 4 relates to said problems)

Note: The professor did not cover how to do a problem like this, and the book does not have a similar problem, nor any other handouts. This definitely was a unique question.

I'm unsure if I should list the units or not within the interval notation.
I can't find a single justification on the web whether or not do such.

Homework Equations



Should I be putting all of #5 and #6 in interval notation? How so?
What would be a proper way to word it?

The Attempt at a Solution



#5 Answer?
(45, 87.5)

#6 Answer?
[0, 45)U(87.5, 100]

Right?

Say that I want to express the time interval during which a particle is moving to the right.
Time is in seconds...

At 0 and between 45 seconds, the particle is moving to the right.
AND
Between 87.5 seconds and 100 seconds, the particle is moving to the right.

Or would I list [0 s, 45 s)U(87.5 s, 100 s]

Basically, this has to do with a physics problem.
Moving to the right means the particle is moving in a positive direction.
There are other times during which it moves in a negative direction (left); that occurs between 45 seconds and 87.5 seconds.
At t = 45s and t=87.5s, y=0
 

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Bio-Hazard said:

Homework Statement



#5 and #6 of the attached pdf on page 5 (graph on page 4 relates to said problems)

Note: The professor did not cover how to do a problem like this, and the book does not have a similar problem, nor any other handouts. This definitely was a unique question.

I'm unsure if I should list the units or not within the interval notation.
I can't find a single justification on the web whether or not do such.

Homework Equations



Should I be putting all of #5 and #6 in interval notation? How so?
What would be a proper way to word it?

The Attempt at a Solution



#5 Answer?
(45, 87.5)

#6 Answer?
[0, 45)U(87.5, 100]

Right?

Say that I want to express the time interval during which a particle is moving to the right.
Time is in seconds...

At 0 and between 45 seconds, the particle is moving to the right.
AND
Between 87.5 seconds and 100 seconds, the particle is moving to the right.

Or would I list [0 s, 45 s)U(87.5 s, 100 s]

Basically, this has to do with a physics problem.
Moving to the right means the particle is moving in a positive direction.
There are other times during which it moves in a negative direction (left); that occurs between 45 seconds and 87.5 seconds.
At t = 45s and t=87.5s, y=0

I am happy with the way you gave your answers - or were you merely quoting the answers section of the file to show us what it should have been?

There is always 0 <= t < 45 especially if you can type one of those snappy "less than or equal to" signs. Very easy with a pen and paper.
 
Are you happy with the "s" unit measurement being involved with the interval notation?

No, I was not quoting. I don't have the answers.
 
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