Kind of a simple question but I don't know how to phrase it well enough to find it using google. So if I have a definite integral like $$\int^{1}_{-1...

I just remembered a problem I read years ago but never found an answer: Find how many 0-digits exist in natural numbers between 1 and 1 million. I am a pr...

How is the ordinal $\omega_1$ defined? I know that it is a supremum of all smaller ordinals, but then $\omega^\omega$ is also a supremum of all smaller or...

I was confused about the relationship between a set of basis vectors in 3D, $ \left\{\hat e_1, \hat e_2, \hat e_3 \right\} $ and their exterior products. ...

I am currently reading Hamming's Numerical Methods for Scientists and Engineers. On pg. 79 he discusses the topic of finding the zeros of a complex a...

I am looking to expand my knowledge on set theory (which is pretty poor right now -- basic understanding of sets, power sets, and different (infinite) car...

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Consider the group $D_4$. Give examples of $D_4$ acting on a set. Attempt: So $|D_4| = 8$. I have come up with a few, but I was wondering what some people...

I got a question given by my lecturer to find the domain and range of this function: $$y=\sqrt{2-x^2}$$ For the domain, we start by restricting the square...

Let $X:\Omega\times[0,T]\longrightarrow \mathbb{R}$ be a non-negative submartingale with cadlag sample paths, $p>1$ and $C>0$. Then I understand tha...