Given vectors, constructing a matrix

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To construct a matrix from given vectors v1, v2, and v3, the choice of using them as columns or rows depends on the context and the specific problem being addressed. It is crucial to maintain clarity and logical progression in your approach, as incorrect setup can lead to errors, especially in exam situations. While some matrix operations yield the same results regardless of orientation, others, such as solving equations, can produce different outcomes. Understanding the application and goal of the matrix is essential for determining the appropriate configuration. Ultimately, ensuring that you are clear on your setup will help you achieve the desired results.
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Homework Statement


Say you've been given vectors v1, v2 and v3.

Homework Equations

The Attempt at a Solution


How do I construct a matrix out of these three vectors? Am I to use the given vectors as columns or rows in a matrix? When does this matter and when does it not? This may be a stupid question, but I haven't been able to find a clear answer. My textbook constructs matrices in both ways, but I'm never clear as to why they construct them as columns or rows. Does it depend entirely on the context and goal of the question? If there's a clear answer for this, I'd appreciate it, thanks.
 
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It depends on the context.
I normally like them stacked in rows of I am treating them like a system.
The main thing is to keep track of your given information and make logical steps to your goal.
 
RUber said:
It depends on the context.
I normally like them stacked in rows of I am treating them like a system.
The main thing is to keep track of your given information and make logical steps to your goal.
So, during an exam you can ruin a question if you incorrectly set the vectors up, right?
 
JesseJC said:
during an exam you can ruin a question if you incorrectly set the vectors up, right?
Maybe it would be, for you may disorder what operations you are doing.
But just like it's mentioned above, you just have to think clearly and make logical steps toward your goal.
 
Do you have a particular application in mind? Have you recently had trouble with this?
Essentially, you are dealing with either one matrix or its transpose. In your notation, you can easily fix any mistakes by adding the ^T to your matrix.

Some applications, like the determinant (if your matrix is square), are the same either way, ## |A| = | A^T| ##.
Others, like Ax = B, might have entirely different solutions.
 
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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