bloodhound

Take a four digit positive number A, reverse the digits to make number B

show that A^2 - B^2 is always divisible by 99

example: A=3785 B=5873

first question in my analysis exam today , dont know why.

i hate definitions

I find cracking necks really impresssive. i would never get into a fight with someone who can crack neck . they are ovbisouly nutters. i am learning to crack neck myself

Proofs nicked from my pure maths lectures

yeah. everything i would say has been said. any number with a decimal form containing repeating block for example 0.12345234234234234234234 can be expressed as a fraction. conversly any rational number must have a terminating or a repeating decimal form.

ok, its sorted then.

spheres exists in a fractional dimension.

Hi. i have a intel 2.3 Ghz laptop

just downloaded pcmark 04 to see whats my laptop like . and i saw one interesting thing in the system details section

u can see that it says Hyperthreading is available but disabled. I never knew it was available , there was no mention of that when i bought the computer etc. Has pc mark diagnosed my computer wrong. is it possible to enable hyper threading in mine>

help

dave, u maybe rite for now. But this mathematics will come very handy in future. Just like Differential and integral calculus was only used to describe motion of bodies relative to time when the tool was invented.

I (personally) dont really see the point to need to visualise numbers. altough I admit its sometimes helpful..

I agree with Mandrake Root , that all numbers are concepts. Aliens on mars may do mathematics differently , but the concept will be the same

This post isnt very helpful is it

try drawing the graph of function f:R -> {0,1} defined by f(x)=1 if x is rational and f(x)=0 if x is irrational. Have some fun.

A: havent watched anime for a while. But i would say Spike from Cowboy Bebop

Q: What is your fav radio station

i still prefer to think of a sphere as a limiting form.

I tried to graph the function implicitly in Maple, which is a very good maths software and weird things begun to happen.

heres the commands.

>with(plots);

>implicitplot(x^y=y^x,x=0..10,y=0..10);

This is the result. Note the graph looks similar to the one above but its all wavy.

Now the strange things happens

i try

>implicitplot(x^y=y^x,x=0..100,y=0..100);

and this is what i get

its all gone wrong.

IF anyone has maple , can you repeat what i have done and see if u get the same result. cheers

sorry dude, thats just too advanced. we are just first year maths students

i looked at question 4 and it didnt make any sense to me as well

My dad is a diplomat [1], he's met the queen[2] and shes met george bush[3]

come to think of it, i can relate to most of the worlds leaders the same path. in three

yes dave. thanks for pointing that out. i was aware of that.

but treating dx/dt as a fraction is probably the better way to teach pple who are challenged in the art of calculus

[math]

\[

\begin{array}{c}

\frac{{dx}}{{dt}} = - ax \\

\frac{1}{x}dx = - a{\rm{ }}dt \\

\ln x = - at + k \\

x = e^{ - at + k} \\

x = e^k e^{ - at} \\

x = Ce^{ - at} \\

\end{array}

\]

[/math]

at the second to last line. we know x=c when t=0 . pluggin the values in we get e^k = C

lim      [u]f(x+h)-f(h)[/u]
h->0         h

that sould be

]

lim      [u]f(x+h)-f(x)[/u]
h->0         h

I WAS about to say the same thing dave. totally agree with u theeere

yes y=e^(kx) is a nice trial solution

but the one i like more is to try

y= Sum [a_nxⁿ] from 0 to inf

but eventuall if y = e^kx is a solution , you would probably just end up with the series form of the exponential.

Biologists think they are Bio-Chemists

Bio-Chemists think they are Chemists

Chemists think they are Physical Chemists

Physical Chemists think they are Physicists

Physicists think they are GOD

GOD thinks he/she is a MATHEMATICIAN

testing

[math]

\[

\sqrt {a^2 + b^2 }

\]

[/math]

[math]

\[

\begin{array}{l}

\bigcup\limits_{i = 1}^n {X_i } = R \\

X_i = \{ \frac{k}{i}:k = Z\} \\

\end{array}

\]

[/math]

we are also talking about the speed of writing data, not just the amount of storange possible.

yeah , u can do nifty things with that like finding i^i or -1^-i etc. etc

How about Euler's Constant?

I read that it's approx 0.5772.... and it's one of the most significant numbers trailing only :pi: (pi)and e (natural log).

if u have a positive' date=' twice differentiable function f whose second derivative is positive on (0,inf)

then the limit as n tends to infinity of

SUM[f(k),k=1 to n'] - Integral[f(x)dx from 1 to n]

exists

if u put f((x)=1/x

the limit above is the eulers constant

i.e 1 + 1/2 + 1/ 3 + 1/4 + ... + 1/n - ln n converges. which is quite remarkable given that if u take about the (- ln n) bit , u get the harmonic series, which diverges.