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3h
comment What did I do wrong when using Jacobian transformation
Hint: What is the domain for the joint density of (X,Y)?,
3h
revised $xf''(x) , xf', f \in L^{2}$ is $f' \in L^{1}$?
derivative in title
3h
revised Find the function whose Taylor series is $\log(x)+\log(x+1)+\log(x+2)+\ldots$
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1d
reviewed Close How long should you study Mathematics each day if you want to get into a graduate school?
1d
reviewed Close Sum of a truncated normal random variable and normal random variable (correlated)
1d
awarded  Revival
1d
comment Orthogonal Operator Infinite Dimensional Inner Product Space
I see. The polarization identity, if you haven't seen it before, is $\langle x,y \rangle = \frac{1}{4}(\|x+y\|^2 - \|x-y\|^2)$.
1d
comment Orthogonal Operator Infinite Dimensional Inner Product Space
Polarization: you can write the inner product in terms of the norm. How else did you prove the finite dimensional case?
1d
comment Weak convergence of continuous functions
@Philip: No, I think we're okay. Remember that $\mu$ is a finite measure.
1d
answered Weak convergence of continuous functions
1d
comment Weak convergence of continuous functions
@This is much healthier: You're right, it does work in the locally compact case also. I'm not sure why I was thinking it didn't. But it only characterizes weak convergence of sequences, not nets. Nevertheless, I guess I'll post it as an answer later.
1d
comment Orthogonal Operator Infinite Dimensional Inner Product Space
Note that the first equivalence is still true in infinite dimensions.
2d
comment Are translates of Gaussians an overcomplete set in $L^2(\Bbb R)$?
@Qiaochu: As defined, I don't think these functions form an algebra. (Note that we are not allowed to horizontally scale the Gaussian.)
Jul
19
answered What is the expectation of a random variable raised to the $n$th power?
Jul
19
answered Fibonacci series, which is most pure mathematically?
Jul
19
revised Given $u \in L^1$, is there approximating sequence $u_n \in L^\infty$ uniformly bounded in $L^p$?
spelling
Jul
19
revised solving the system
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Jul
19
revised “Deep” maths books in certain subjects
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Jul
19
revised Check: Find the Fourier transform of $f(x)=ax+b$ with $a,b \in \Bbb R$.
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Jul
19
comment Finding the probability of ever visiting a transient state for a zero-seeking device for a Markov Chain?
I suspect induction on $k$ will do the trick.