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choco_addicted

South Korea

An undergraduate in South Korea. I major in Mathematics Education.

My picture is attributed by 역보, a contributer in Libre Wiki, and distributed under Creative Commons Attribution-ShareAlike 3.0 Unported.

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108
$100$-th derivative of the function $f(x)=e^{x}\cos(x)$
math.stackexchange.com

32
Prove the following trigonometric identity without a calculator involved
math.stackexchange.com

18
How to calculate $ \sum_{n=1}^{15}n(n!) = ? $
math.stackexchange.com

14
How to prove that $k^3+3k^2+2k$ is always divisible by $3$?
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9
Exponential (to the power of a logarithm)
math.stackexchange.com

9
how to prove that $2^n = (n+1)(n+2)(n+3)$ has no solution when $n>0$?
math.stackexchange.com

9
Find $3a+b+3c+4d$ if $\left(\begin{smallmatrix}-4&-15\\2&7\end{smallmatrix}\right)^{100}=\left(\begin{smallmatrix}a&b\\c&d\end{smallmatrix}\right)$.
math.stackexchange.com

9
How should I use the pronoun 당신?
korean.stackexchange.com

9
Decide whether the series ${\sum_{n=1}^{\infty} \frac{1+5^n}{1+6^n}}$ converges or diverges
math.stackexchange.com

8
Solve $e^{4z} +e^{3z} + e^{2z} + e^z + 1 = 0$.
math.stackexchange.com

8
Weight of watermelons after percentage of water is evaporated.
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8
Is there a special meaning of '이' when added on to names?
korean.stackexchange.com

7
Discuss the differentiability of $e^{-|x|}$?
math.stackexchange.com

7
Let $P$ be a 4-th degree real polynomial with 5 conditions given. How to compute $P(4)$?
math.stackexchange.com

7
Find the value of $\frac{1}{20} + \frac{1}{30} + \frac{1}{42} + \frac{1}{56} + \frac{1}{72} + \frac{1}{90}$
math.stackexchange.com

7
Evaluate $\lim_{x \to 0} \frac{\tan(\tan x)-\sin(\sin x)}{\tan x-\sin x}$
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7
How would you solve this system if linear equations in 3 variables?
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7
Does $\sum_{n=1}^\infty {\frac{ \sin(\frac{n\pi}{6})}{\sqrt {n^4 + 1}}}$ converge?
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7
Find $a^{100}+b^{100}+ab$
math.stackexchange.com

6
Can I write "마음을 잡수시다"?
korean.stackexchange.com

6
Is $x^4 + 4$ irreducible in $\mathbb{Z}_5$?
math.stackexchange.com

6
Why $\sum_{n=1}^\infty {\ln(n^2) \over n^2 }$ converges?
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6
Should I use L'Hôpital
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6
Compute $\sum\limits_{n=1}^{\infty} \frac1{1+x_n}$ if $x_1>0$ and $ x_{n+1} = x_n ^2 + x_n $
math.stackexchange.com

6
Recovering a quadratic polynomial from three values using calculus
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6
Proof that $\sum_{i=0}^n 2^i = 2^{n+1} - 1$
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6
integrate $\cos(x)+\sqrt{1+x^2}\sin^3(x)\cos^3(x)$
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6
If $f'(2) = 7$ , calculate the $\lim_{h\to 0} \frac{f(2+3h)-f(2-5h)}{h}$
math.stackexchange.com

6
If $ \frac{x}{b-c} = \frac{y}{c-a} = \frac{z}{a-b}$, Prove that $x+y+z$ $=0$
math.stackexchange.com

5
$f(x)$ is a polynomial and $f(\alpha)^2+f'(\alpha)^2=0$. Find $\lim_{x\to\alpha}\frac{f(x)}{f'(x)}\left\lfloor\frac{f'(x)}{f(x)}\right\rfloor$
math.stackexchange.com

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