2,890 reputation
516
bio website
location Florida
age 18
visits member for 1 year, 7 months
seen Jun 26 at 5:39

highschooler and recreational mathematician


Jul
2
awarded  Curious
Jun
2
awarded  Good Question
May
7
comment Evaluating the infinite series $\sum\limits_{n=1}^\infty(\sin\frac1{2n}-\sin\frac1{2n+1})$
@user45105 $a_k=\sin(1/(2k))\implies a_{k+1/2}=\sin(1/(2(k+1/2)))=\sin(1/(2k+1))$
May
7
comment How come $32.5 = 31.5$?
@MathGems unfortunately it is not mine.
Apr
20
awarded  Popular Question
Feb
15
awarded  Civic Duty
Feb
1
comment The strange (for me) case of Mod of Iota.
we can define $|z|$ by identifying $z\in\mathbb{C}$ with $(\Re\{z\},\Im\{z\})\in\mathbb{R}^2$ and by analogy with $|\cdot|:\mathbb{R}\to\mathbb{R}^{\ge0}$ defining it as the Euclidean distance from $(\Re\{z\},\Im\{z\})$ to $(0,0)$
Feb
1
comment The strange (for me) case of Mod of Iota.
how the hell are we cheating our way out of a paradox? there are uncountably many $z\in\mathbb{C}$ that satisfy $|z|=1$ -- consider $t\mapsto\exp(it)$. This is true. You are wrongly assuming that $|i|=1\implies i=\pm1$ holds for complex numbers when it clearly does not.
Feb
1
comment The strange (for me) case of Mod of Iota.
$|x|=1\implies x=\pm1$ is only true for $x\in\mathbb{R}$; when we generalize modulus to $\mathbb{C}$ this is no longer true as you pointed out.
Jan
25
comment Why is an orthogonal matrix called orthogonal?
the comment tells you why: they are of no particular interest... if a matrix has orthogonal columns then it necessarily is of the form $UD$ where $U$ is orthogonal and $D$ is diagonal
Jan
24
comment Why is an orthogonal matrix called orthogonal?
"It might be tempting to suppose a matrix with orthogonal (not orthonormal) columns would be called an orthogonal matrix, but such matrices have no special interest and no special name." en.wikipedia.org/wiki/Orthogonal_matrix#Matrix_properties
Jan
24
comment Is this $\epsilon-\delta-$proof correct?
(+1) exactly what I was in the midst of typing
Jan
24
comment Is this $\epsilon-\delta-$proof correct?
you can also use \operatorname{Re} i.e. $\operatorname{Re}$
Jan
24
comment Is this function well-defined or just an abuse of notation?
the nonsense here is that you're conflating free and bound variables (namely the two different $x$'s)... in general you don't want to be so vague
Jan
20
awarded  Organizer
Jan
15
comment Proving nondifferentiability at all points of a continuous function
note you can get arbitarily close to $x$ using $n(2^n-1)/2^n$
Jan
15
reviewed Approve suggested edit on Matrix Groups dealing with $GL_n(\mathbb{R})$
Jan
15
revised factor $z^7-1$ into linear and quadratic factors and prove that $ \cos(\pi/7) \cdot\cos(2\pi/7) \cdot\cos(3\pi/7)=1/8$
deleted 7 characters in body
Jan
13
answered How can I solve $y^{3}-3y^{2}+2=0$?
Jan
12
reviewed Approve suggested edit on Every inner product space is a normed space which is also a metric space