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Studying maths in a higher semester.


4m
comment Linear Transformation on $\mathbb{R}^6$
@ap21 Very good. Everything is correct. For a counter-example to (C) chose the columns of $T$ such that $e_1, e_3$ and $e_5$ are linearly dependent.
18h
comment How to calculate probability of users generating distributed events reaching n events per 15 minutes?
Just for clarification: The model is that $20\%$ of the $N$ users will cause $1$ "query" event within a duration of $5$ minutes. $N$ is to be determined from the number of installations divided by the time window you see fit, sliced into $5$-minute slices. The relevant Poisson-parameter is $\lambda = \frac15 + \frac4{25} + \frac{16}{125}$ (the probability of access in at least one of the three $5$-minute slices we are watching.)
18h
answered Easy: Graphs of Straight Line
18h
revised Question about a proof of Riemann localization theorem
added 494 characters in body
18h
answered Question about a proof of Riemann localization theorem
18h
comment A lower bound for $\log\left( \frac{a+x^2}{b+x^2}\right)$
And for what $x$ does the bound have to hold?
19h
comment To show that $X = (0,1]$ is complete .
Also the one in $[0,\infty)$? Even if, the problem remains.
19h
comment To show that $X = (0,1]$ is complete .
No. You just move to another space, $([1,\infty), |\cdot|)$ and show convergence of anoter sequence. This proves nothing about the original space and sequence.
19h
reviewed Approve to find the determinant of a matrix given the roots of an equation
19h
revised Improvement IMO 1988 $f(f(n))=n+1987$
edited tags
19h
revised Is it possible to prove that $\text{tr}(AB)=\text{tr}(BA)$ without using matrices?
edited tags
20h
comment What is the correct form of De Morgan's Law in logic?
I suggest you write an e-mail to the author, Simon Colton to notify him of the error.
20h
comment What is the correct form of De Morgan's Law in logic?
@Michiel You should make a truth table to verify what is wrong with your source. If $Q = \text{false}$ and $P = \text{true}$, the RHS evaluates to $\text{false}$ but the LHS evaluates to $\text{true}$.
20h
comment Is it a subspace or not?
@user211273 Yes, you can even take concrete values such as $(1,1,0) + (\omega_3,1,0) \notin \mathcal S_2$.
21h
answered Floating-point arithmetic error
21h
comment What is the line of greatest slope of a plane?
I'm afraid you'll have to give some context. Technically, a vector has no slope unless you give it a meaning by defining what you see as a slope of a vector, or a line with a given direction vector.
21h
comment Help reading a scatterplot
@copper.hat You might want to put that up as an answer, since it basically covers everything ;) (+1)
21h
answered Is it a subspace or not?
21h
comment Prove that Boolean algebra P(S) is isomorphic with the product.
Welcome to math.SE: since you are new, I wanted to let you know a few things about the site. In order to get the best possible answers, it is helpful if you say in what context you encountered the problem, and what your thoughts on it are; this will prevent people from telling you things you already know, and help them give their answers at the right level. Also, many find the use of imperative ("Prove", "Solve", etc.) to be rude when asking for help; please consider rewriting your post.
21h
answered Linear Transformation on $\mathbb{R}^6$