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Ahmed S. Attaalla

I put my headphones in and indulge in the world of mathematics. Class of 2017 , Culver City High School. Class of 2021, University of California, Irvine.

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Top Questions
25 votes

How to know whether Lagrange multipliers gives maximum or minimum?

calculus multivariable-calculus optimization lagrange-multiplier asked Dec 30 '16 at 1:26
math.stackexchange.com

22 votes

Why does gravity act at the center of mass?

homework-and-exercises newtonian-mechanics newtonian-gravity asked Apr 26 '17 at 0:29
physics.stackexchange.com

14 votes

How to evaluate $\int_0^1\int_0^1 \frac{1}{1-xy} \, dy \, dx$ to prove $\sum_{n=1}^{\infty} \frac{1}{n^2}=\frac{\pi^2}{6}$.

calculus multivariable-calculus riemann-zeta asked Aug 6 '16 at 17:42
math.stackexchange.com

12 votes

An application of the Inclusion Principle to Chemistry? (Proof Verification)

combinatorics proof-verification inclusion-exclusion chemistry asked Nov 28 '17 at 23:26
math.stackexchange.com

10 votes

Sequence related to solutions of the equation $x^x=c$

sequences-and-series limits lambert-w asked Jan 4 '16 at 4:42
math.stackexchange.com

9 votes

Evaluate $\sum_{n=0}^{\infty} \frac{n!}{(n^2)!}$

calculus sequences-and-series asked Aug 7 '16 at 18:02
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9 votes

Nonlinear spring $F=-kx^3$

homework-and-exercises newtonian-mechanics spring asked May 8 '17 at 1:30
physics.stackexchange.com

8 votes

Derivative of Lambert W function.

calculus asked Oct 10 '15 at 16:23
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7 votes

Why is the sum of the digits in a multiple of 9 also a multiple of 9?

elementary-number-theory divisibility asked Apr 5 '15 at 23:14
math.stackexchange.com

7 votes

Using the digits $1-9$ each only once find the closest sum to $1000$.

recreational-mathematics asked Jan 11 '17 at 21:12
math.stackexchange.com

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Top Answers
26
Is there a unique polynomial function $f(x)$ of degree $\lt n$ such that $f(n) = a_n$ where $\{a_n\}$ is a sequence?
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18
An irrational number $x$ such that $x^x$ is rational
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16
Prove the theorem on analytic geometry in the picture.
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15
How do I prove that powers of 5 are the sum of two squares using mathematical induction
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14
What does this series converge to, if anything?
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13
$x+\ln(x)=0$, what is $x$?
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12
Integration of Sinc function
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12
Find the sum of an alternating, non-geometric series
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11
Does there exist $a \in \mathbb{Q}$ such that $a^2 - a + 1$ is a square?
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10
Does this pattern have anything to do with derivatives?
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10
Sum $\frac {1}{9} + \frac {1}{18} +\frac {1}{30} +\frac {1}{45} +\frac {1}{63} \ldots$
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9
Finding out the limit $\lim_{a \to \infty} \frac{f(a)\ln a}{a}$
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9
Inverse of a factorial
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8
Is there a formulaic way to go from $\sum_{k=1}^{n} \frac{1}{k}$ back to $n$?
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8
How to show this fraction is equal to 1/2?
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8
What is $\int_0^1\frac{x^7-1}{\log(x)}\mathrm dx$?
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8
Solve $\lim_{n\to \infty} \int_{0}^{\pi\over3} {{\sin^nx}\over \sin^nx+\cos^nx}dx$
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8
Find integral $\int_0^1 \frac{\ln x}{1 - x^2} \mathrm{d}x$
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8
Power term calculated from preceding terms
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7
Find $\sum_{n=1}^{\infty}$ $\frac{n^{2}}{\left(n+1\right)\left(n+2\right)\left(n+3\right)\left(n+4\right)}$
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7
In which order do I graph transformations of functions?
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7
How to solve this logarithmic equation through algebraic manipulation?
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7
Double Integral : $\int^{1}_{0}\int^{1}_{\sqrt{y}}e^{x^3}dxdy$ without $\Gamma$ function.
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7
Why does combining $\int_{-\infty}^{\infty} e^{-x^2} dx\int_{-\infty}^{\infty} e^{-y^2} dy$ into a $dx\,dy$ integral work?
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6
A proof for the identity $\sum_{n=r}^{\infty} {n \choose r}^{-1} = \frac{r}{r-1}$
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6
Definite integral of $\int_{0}^{\pi}{\frac{dx}{1+\sin^2x}}$ with u-substitution?
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6
Find the limit of the following expression:
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6
Notation for every odd integer number
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6
Formula for $1^k+2^k+3^k…n^k$ for $n,k \in \mathbb{N}$
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6
How to calculate $5^{2003}$ mod $13$
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