No known formula ??? (2 Viewers)

CrashOveride · Feb 18, 2004

Hi everybody,

im using Patel's 2nd edition book for MAX2 and i came across something today when doing some work with polynomial questions. If anyone has this book, what im talking about is the worked examples on page 180.

It's got @, #, & are the roots of x^3 - 2x^2 + x + 3 = 0
evaluate @^4 + #^4 + &^4

In patel's working, he states " there is no known formula that relates (summation)@^4 with (summation)@ "

so ok he goes ahead multiplies throughout by x, makes x^4 the subject and substitutes...and bango...a legitimate way indeed.

However, in class today we quite quickly worked out (stumbled?) onto an actual formula for it. Found it strange that he said NO known formula existed ???

PS. You guys recommend getting more than the one 4u textbook? Im using patel's and its OK, but i heard Fitzpatrick's book was quite good also ?

abdooooo!!! · Feb 18, 2004

took to me awhile to understand what you're going on about. symbols are too weird to understand on the net.

think its not known means its not famous, or commonly used to workout that problem... because the substitute method is simpler.

yeah fitz is good... the more the better.

abdooooo!!! · Feb 18, 2004

Originally posted by CrashOveride
However, in class today we quite quickly worked out (stumbled?) onto an actual formula for it.

but how did you do it quickly? i haven't tried it doing it that way... but just looking at it seems hard to factorise... i mean a power of 4... lol.

Grey Council · Feb 18, 2004

*gets ready to take a dig at abdooo*

yeah, so whats this formula you guys stumbled upon? hehe, tell us, and we'll tell you if its been discovered or not. ( lol,

i'm sure Abdoooo won't use the formula for anything else, heheheh).

besides, if patel says there are no formulas, then there are none that you can use in hte HSC syllabus. So it doesn't matter if you know a new method or not, Abdooooo will still beat you in the HSC. (thats what he thinks anyway

)

lol

abdooooo!!! · Feb 18, 2004

Originally posted by Grey Council
*gets ready to take a dig at abdooo*

yeah, so whats this formula you guys stumbled upon? hehe, tell us, and we'll tell you if its been discovered or not. ( lol, i'm sure Abdoooo won't use the formula for anything else, heheheh).

besides, if patel says there are no formulas, then there are none that you can use in hte HSC syllabus. So it doesn't matter if you know a new method or not, Abdooooo will still beat you in the HSC. (thats what he thinks anyway )

lol

what are you saying?!?! when did i think im gonna beat that dude who i don't even know.

you're funny one aren't you... lol

and with the formula thingy... its not actually a formula... i mean its just manipulating of a^4 + b^4 + c^4 into the roots relationships ie a + b + c, ab + ac + bc, and abc.

im assuming you don't understand the question because of the weird symbols... let me take an easier example to illustrate lol: a^2 + b^2 + c^c = (a + b + c)^2 - 2(ab + ac + bc)

so its not some special formula like the pythagoras' theorem... you don't have to discover how to manipulate algebra you know... algebra is already invented long ago.

Xayma · Feb 18, 2004

Originally posted by abdooooo!!!
algebra is already invented long ago.

Grammar invented ago long as well

abdooooo!!! · Feb 18, 2004

Originally posted by Xayma
Grammar invented ago long as well

what? what grammar? you mean your mum^2???

this is the math forum for a reason you know... cause we're crap english

Xayma · Feb 18, 2004

Originally posted by abdooooo!!!
cause we're crap english

lol thats just too wrong because its implying that were are of complete english descent.

abdooooo!!! · Feb 18, 2004

Originally posted by Xayma
lol thats just too wrong because its implying that were are of complete english descent.

damn you... so you think you're good at english eh??? go to the ext2 english forum and argue with me there... i'll be waiting... oh crap i don't do ext 2.

aud · Feb 18, 2004

Originally posted by CrashOveride
Hi everybody,

im using Patel's 2nd edition book for MAX2 and i came across something today when doing some work with polynomial questions. If anyone has this book, what im talking about is the worked examples on page 180.

It's got @, #, & are the roots of x^3 - 2x^2 + x + 3 = 0
evaluate @^4 + #^4 + &^4

In patel's working, he states " there is no known formula that relates (summation)@^4 with (summation)@ "

so ok he goes ahead multiplies throughout by x, makes x^4 the subject and substitutes...and bango...a legitimate way indeed.

However, in class today we quite quickly worked out (stumbled?) onto an actual formula for it. Found it strange that he said NO known formula existed ???

PS. You guys recommend getting more than the one 4u textbook? Im using patel's and its OK, but i heard Fitzpatrick's book was quite good also ?

I bought Patels, but the school gave us Fitz's and the two Coroneos' ones... I prefer Patel, and like the way he explains things, but a lot of the stuff is too easy and he doesn't explore 'harder' questions like in Fitz and Coroneos

Originally posted by abdooooo!!!
what? what grammar? you mean your mum^2???

this is the math forum for a reason you know... cause we're crap english

Oi - we're not all crap at English here~!

edd91 · Feb 18, 2004

if you put the roots in brackets (x-a)(x-b) and expand you will get a relationship

KeypadSDM · Feb 18, 2004

Originally posted by edd91
if you put the roots in brackets (x-a)(x-b) and expand you will get a relationship

Yeah, we know. It's the sum of the roots, sum of the root in pairs, sum of the roots in triples and so on.

abdooooo!!! · Feb 18, 2004

Originally posted by edd91
if you put the roots in brackets (x-a)(x-b) and expand you will get a relationship

lol. and?

wait let me try that power of 4 thingy by expanding with algebra to get the formula in relationship form... if im not back after 20mins i gave up.

KeypadSDM · Feb 18, 2004

Note:

A4 + B4 + C4 = (A + B + C)4 - 4( A + B + C)2(AB + BC + AC) + 2(AB + BC + AC)2 + 4ABC(A + B + C)

As far as I'm concerned, that relationship doesn't purely rely on Sum[A], rather Sum[A], Sum[AB] and Sum[ABC].

Which means the statement is correct, there is no equation.

abdooooo!!! · Feb 18, 2004

Originally posted by KeypadSDM
Note:

A4 + B4 + C4 = (A + B + C)4 - 4( A + B + C)2(AB + BC + AC) + 2(AB + BC + AC)2 + 4ABC(A + B + C)

As far as I'm concerned, that relationship doesn't purely rely on Sum[A], rather Sum[A], Sum[AB] and Sum[ABC].

Which means the statement is correct, there is no equation.

wow did you just do that?? how fast are you? i think i've done something wrong...

can you explain to me more clearly why the that statement is true... i don't think im following you... im a bit confused here.

KeypadSDM · Feb 18, 2004

I probably got it wrong. I'll type it up in the morning. I'm going to sleep.

But I'll explain the statement:

" there is no known formula that relates (summation)@^4 with (summation)@ "

This means, there is no formula where:

A4 + B4 + C4 + ... + n4 = f(A + B + C + ... n)

But there is a formula where there are multiple functions on the right hand side, in the form:

f(A + B + C + ... n)
g(AB + BC + CD + ... nA)
h(ABC + BCD + CDE + ... nAB)
etc.

abdooooo!!! · Feb 18, 2004

Originally posted by KeypadSDM
But I'll explain the statement:

" there is no known formula that relates (summation)@^4 with (summation)@ "

im thinking about this statement... it doesn't make sense... i mean is this not a commonly used formula to solve power of 2: a^2 + b^2 + c^2 = (a + b + c)^2 - 2(ab + ac + bc)... but that doesn't purely rely on sum(a) does it? i mean nothing does... im confused... patel is an idiot as far as im concerned lol.

freaking_out · Feb 18, 2004

its prolly just a short cut formula that might b worthwile remembering- the patel guy does that sometimes.

abdooooo!!! · Feb 18, 2004

Originally posted by freaking_out
its prolly just a short cut formula that might b worthwile remembering- the patel guy does that sometimes.

what are you saying?? shortcut? if you do it the relationship way its the longest cut you can get... but the statement of patel is ultmately flawed... unless he is talking about something else instead of polynomial roots and their relationship.

at first i thought the statement meant in the form of sum[a], sum[ab] and sum[abc]... but then keypad started talking about only sum[a] then im confused... now i've re-read the statement it just does not make sence anymore.

freaking_out · Feb 18, 2004

Originally posted by abdooooo!!!
what are you saying?? shortcut? if you do it the relationship way its the longest cut you can get... but the statement of patel is ultmately flawed... unless he is talking about something else instead of polynomial roots and their relationship.

at first i thought the statement meant in the form of sum[a], sum[ab] and sum[abc]... but then keypad started talking about only sum[a] then im confused... now i've re-read the statement it just does not make sence anymore.

don't worry if ur confused- that can happen when ur trying to read/type maths ova the net using funny symbols. LoL

No known formula ??? (2 Viewers)

Active Member

Banned

Banned

Legend

Banned

Lacking creativity

Banned

Lacking creativity

Banned

Member

Member

B4nn3d

Banned

B4nn3d

Banned

B4nn3d

Banned

Saddam's new life

Banned

Saddam's new life

Users Who Are Viewing This Thread (Users: 0, Guests: 2)