4,926 reputation
11020
bio website jpmccarthymaths.com
location University College Cork, Ireland
age 29
visits member for 2 years, 11 months
seen 1 hour ago

An assistant lecturer at the Cork Institute of Technology. I am also a PhD student of mathematics at University College Cork, Ireland. I hold a BSc and an MSc from UCC. A recent cv, (June 2014) may be found here.

https://jpmccarthymaths.files.wordpress.com/2010/07/resume.pdf


1d
comment Trying to subtract 2 fractional
...also I would like to point out that the question was edited heavily since I answered.
1d
comment Trying to subtract 2 fractional
An axiom is a fact that we assume and a theorem is a fact that we can prove from axioms.
1d
answered Trying to subtract 2 fractional
1d
comment Find the area bounded by $x+y=3$ and the coordinate axes.
Note if you graph the situation you have a triangle with base 3 and perpendicular height 3...
1d
comment Can you cancel out a term if equal to zero?
I have banned the word "cancel" from my classes also.
2d
comment Second Order Linear Differential Equations
$y_T(x)=pxe^x$ is also in the complementary/homogenous solution... try $y_T(x)=px^2e^x$.
2d
comment If w is a complex root of 1. Find the value of w^4+w^8
...or perhaps the textbook defined $\omega$ as a particular cube root of unity...
Oct
16
comment How to find line parallel to direction vector and passing through a specific point?
No... different values of $t$ give you different points along the line. $P+t\mathbf{v}$ is the answer. Draw a picture.
Oct
16
comment How to find line parallel to direction vector and passing through a specific point?
$L\equiv P+t\mathbf{v}$ should do the trick.
Oct
16
comment Analogous of Markov's inequality for the lower bound
After a Google en.wikipedia.org/wiki/Paley%E2%80%93Zygmund_inequality
Oct
16
comment How many perfect shuffles are needed to go back to initial state?
The inverse shuffle is of course OK to study.
Oct
16
comment How many perfect shuffles are needed to go back to initial state?
Yes this is correct sorry I was working mod 8 by mistake.
Oct
16
comment $f(x)=x^m+1$ is irreducible in $\mathbb{Q}[x]$ if only if $m=2^n$.
@SebastianSchoennenbeck ?
Oct
16
comment How many perfect shuffles are needed to go back to initial state?
@Nimda What about the $2^n$ card then? It should stay fixed but for say $n=3$ the 8th card goes to card 7... this is the piecewise problematics that I was dealing with...
Oct
15
revised How many perfect shuffles are needed to go back to initial state?
added 6 characters in body
Oct
15
comment How many perfect shuffles are needed to go back to initial state?
I had something like this and failed to implement it as easily as you. I think what happened was that I had a piecewise definition mod something and didn't quite realise I could do it in one go and do my mod stuff later. I am very happy with my answer but to be honest yours is just way more straightforward so I am compelled to give you plus one!
Oct
15
comment How many perfect shuffles are needed to go back to initial state?
This needs a tweaking. We need $f(1)=1$ but with this you have $f(1)=2+1=3$...
Oct
15
revised How many perfect shuffles are needed to go back to initial state?
deleted 75 characters in body
Oct
15
revised How many perfect shuffles are needed to go back to initial state?
deleted 75 characters in body
Oct
15
answered How many perfect shuffles are needed to go back to initial state?