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1d
comment Find the limit $ \lim_{n \to \infty}\left(\frac{a^{1/n}+b^{1/n}+c^{1/n}}{3}\right)^n$
I have edited your answer as it was quite startling to see such huge fonts. If you want to see the $\TeX$ I used, you can right click on the math and select "Show Math As -> TeX Commands"
1d
revised Find the limit $ \lim_{n \to \infty}\left(\frac{a^{1/n}+b^{1/n}+c^{1/n}}{3}\right)^n$
deleted huge and large fonts, aligned equations, change e^x wiith exp(x), changed log to \log
1d
comment Number Theory $8 \mid (a^2-b^2)$ for $a$ and $b$ both odd
Even easier: $a \in \{1,3,5,7\} \implies a^2 \equiv 1 \pmod{8}$.
May
18
revised Proof using trigonometry that circle circumference is $2 \pi R$
fixed typos
May
18
comment Proof using trigonometry that circle circumference is $2 \pi R$
I should also mention that Michael Hardy mentioned that the circumference of a circle and its length are often confused, and I admit that I use the two terms interchangeably here. What I give up in precision, I make up for in getting my point across.
May
18
answered Proof using trigonometry that circle circumference is $2 \pi R$
May
18
comment Proving an inequality: $|1-e^{i\theta}|\le|\theta|$
+1: IIRC, the OP's problem appears in "Berkeley Problems in Mathematics" and your hint appears as their solution.
May
18
comment A binary quadratic form: $nx^2-y^2=2$
Related.
May
17
awarded  Constituent
May
17
comment Proof using trigonometry that circle circumference is $2 \pi R$
What is $\pi$ if not the ratio of a circle's circumference to the length of its diameter?
May
17
comment Proof f(x) is continuous given $x$ rational and irrational.
Hint: Show that if $a \neq \frac{1}{2}$, then $\displaystyle \lim_{x \to a} f(x)$ does not exist.
May
17
comment Proof using trigonometry that circle circumference is $2 \pi R$
How do you define $\pi$?
May
17
comment Using the hypothesis $\frac{1}{a}+\frac{1}{b}+\frac{1}{c}=\frac{1}{a+b+c}$ to prove something else
+1, though I would add the words "Without loss of generality" before $a = -b$. The reason is that it may well not be the case that $a = -b$, but we know at least one of $a = -b, b = -c$, or $a = -c$ occurs, and all cases are dealt with similarly.
May
16
comment How to prove that $1/n!$ is less than $1/n^2$?
Correction: the induction works for $n \geq 4$ as $3^2 \not< 3!$.
May
16
reviewed Approve suggested edit on Test of convergence of $\int_{-\infty}^{\infty} \dfrac{x^6+6}{x^8+8}dx$
May
16
answered Legendre symbol proof
May
16
revised Solving systems of equations using matrices
added 589 characters in body
May
16
comment Solving systems of equations using matrices
I'm not sure I understand what you mean. Gauss-Jordan gives you a method for reducing all augmented matrices regardless of how messy the matrix. In other words, if you always follow the steps of Gauss-Jordan, you will eventually arrive at a matrix which is in reduced row echelon form.
May
16
comment Piecewise defined integration
$f_n(x) = \frac{n}{2} \cdot 1_{\left[ - \frac{1}{n}, \frac{1}{n} \right]}(x)$, where $1_A(x)$ is the indicator function.
May
16
answered Solving systems of equations using matrices