5,775 reputation
31746
bio website ophirgame.com
location United States
age 71
visits member for 3 years, 1 month
seen Apr 6 at 21:51

(update) - I'm having a board game published! We'd appreciate your support on Facebook or on Twitter, as we prepare for a Kickstarter campaign in early 2014.


I hereby commit to contributing to this site without any rudeness, sarcasm, accusation, or any other unloving speech.


Apr
6
comment Proving $\sqrt 3$ is irrational.
Getting a downvote two years later - priceless!
Mar
6
awarded  Yearling
Mar
3
comment Prove that any palindrome with an even number of digits is divisible by 11.
You might be making this too difficult. Do you know the basic test for divisibility by $11$?
Feb
21
awarded  Nice Question
Jan
8
comment Probability that a chosen number will be a Fibonacci number
Natural density on wikipedia
Jan
7
comment The Curve in $R^n$
I would upvote this, but you have $8008$ rep...
Jan
6
comment “Bad” Mathematics in Movies
Related Huff post article
Jan
6
comment Show that the set $K=[0,1]$ is compact in $\Bbb{R}$
Possibly because you have not shown any thought or effort.
Dec
19
comment Derive $y=x\cos^3(5x+1)$
Sounds like you should do a web/video search of "chain rule", Dipok!
Dec
19
comment rank of a matrix series
@Shi/Sivaram/Marvis/17762/etc. - one day, your pride will destroy you. You are intelligent, and maybe more than most in these parts, but the cancerous attitude that your embrace can only end in loneliness and misery. Good luck out there.
Dec
18
comment Find both pairs of numbers that satisfy $\gcd(x,y)= \frac{1}{5}y$ and $x=y-3$
An ordered pair, in this context, is the gcd of said pair. Also, good to see some color back in these parts!
Dec
18
comment If $x^2+y^2=z^2$ has a solution then $5$ divides $xyz$
@EpicGuy: all this talk about "divides" kinda implies that we're dealing with integers only (which we are)...
Dec
18
comment In any Pythagorean triplet at least one of them is divisible by $2$, $3$ and $5$.
Square $1,2,3,4,5$. Then divide each by $2,3,5$ and consider their remainders.
Dec
17
comment Parenthesis vs brackets for matrices
Welcome back, @BillDubuque!
Dec
14
comment Are the following statements TRUE OR FALSE:
Why do you think that they are false?
Dec
14
comment “Well defined” function - What does it mean?
Fair enough, but it looked like you were trying to teach above... =)
Dec
14
comment “Well defined” function - What does it mean?
@Ami: yes, but don't you think you should verify that for yourself?
Nov
20
comment Why Euler relation $\;e^{(ix)}=\cos(ix)+\sin(ix)\;$ can be writen as $\;e^{ix}=\cos(x)+i\sin(x)$?
Also, $e^x \neq \sin(x) + \cos(x)$...
Nov
20
comment Counting - puzzle question
When you put in that way, this "Devil" character sounds like a real jerk!
Nov
19
comment Does $\langle(4,4,4),(1,2,2)\rangle=\langle(1,2,1),(1,0,1)\rangle$?
Your sentence starting with "For instance... is sufficient to prove that the claim is false. Why bother with all the other stuff?