Apr 28, 2020 · I'm self-learning Linear Algebra and have been trying to take a geometric approach to understand what matrices mean visually. I've noticed this matrix product pop up repeatedly …

Why is $1$ not considered a prime number? Or, why is the definition of prime numbers given for integers greater than $1$?

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Jan 15, 2013 · Possible Duplicate: How do I convince someone that $1+1=2$ may not necessarily be true? I once read that some mathematicians provided a very length proof of $1+1=2$. Can …

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How do I calculate this sum in terms of 'n'? I know this is a harmonic progression, but I can't find how to calculate the summation of it. Also, is it an expansion of any mathematical function? 1 ...

Feb 3, 2021 · So that's the "proof". The failure is at step 5, where you say that pq = pr p q = p r implies that q = r q = r; that's true only if you know p p is nonzero. For instance 0 ⋅ 5 = 0 ⋅ 7 0 ⋅ …

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Nov 28, 2019 · Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and …