to be very honest it's over 15 yrs since i did maths.. u are right, i was mixing up of square rooting negative numbers.. which is totally different.. and if i remembered correctly, it is still possible square rooting negatives.. which was in advance maths...Originally Posted by snootyjim
but never mind about that..
can any1 refresh my memory whether it is possible using matrix for this kind of equations.. or is this totally different???
not
2(x-2)^2 + 12 then
cheers. and many thanks..
Well ^^^ that above is technically factorising the equation, but surely not what you meant, no? When talking about quadratics, factorising normally means finding the roots. At least, that's what I assumed.
Anyway, it's not obviously factorisable (to me, at least) in terms of putting things in brackets like this:
(ax + b)(cx + d)
But the roots are:
x = 2 + sqrt(6)
x = 2 - sqrt(6)
irth1ing (07-10-2009)
lol.. you a true mathematician.
i have totally forgotten how tosimplify [8+-(96)^(1/2)]/4
cheers and many thanks.
I'm not sure why you'd want to bring in matrices to this. But yes, you can root negative numbers, the square root of minus one is i. The quadratic equation is probably the quickest and simplest method for solving these problems.
irth1ing (07-10-2009)
oh this just bring back memories .. before, if i remembered correctly, matrices can solve x amount of variables and constants, and it seems really simple to use.. ( i said before.. now i don't have a clue..lol) that's why i was asking...
the quadratic equation is a simplified equation, which does not explain how the answers are derived.. therefore , though it gives you the correct answers, but does not shows you how.. if you know what i mean.. i suppose you can draw the graph to pinpoint the answers, at least that shows you how the answer is derived.. i think..
lol.. this is going over my head..
as you a physicist, i definately take your words for it..
i want to thank you all in helping..
cheers every1..
Yeah that's right, I vaguely remember using algebra (and the aforementioned mysterious "i" to solve roots of negative numbers), but it's not really a big deal. I've never used matrices (dropped maths before that), but I've definitely factorised equations so I wouldn't worry about that.
Also, it's worth saying that the quadratic formula isn't really the best method because you're looking to factorise the equation, rather than solve it - although I admit that if you solve it you can probably factorise it fairly easily.
To be honest though, I never understood how to "complete the square" for some reason... I just used every other method going instead - so maybe I'm not the best person to be commenting
I'd like to think that with a degree in electrical engineering, I'd be able to solve that.
So, I'm not going to try. Ignorance is bliss.
Looks like everyone else has it covered though. Keep up the good work, everyone!
PHP Code:$s = new signature();
$s->sarcasm()->intellect()->font('Courier New')->display();
TheAnimus (07-10-2009)
Ohh, i see what you mean. Yep, you can use a matrix to solve a series of simultaneous equations, but as far as i can remember they need to be linear. So you'd have say:
2x + 5y = 9 and 3x + 2y = 1 and you could bung them into a matrix (or three) to solve for both x and y.
As for the quadratic formula, it's not really fair to call it simplified, it does exactly what it needs to and doesn't claim to be anything more. It will solve any real or complex quadratic.
http://www.mathsisfun.com/algebra/qu...erivation.html
(note my location, i'm not a physicist yet!)
Yup - that's why Matrix Algebra and Linear Algebra are basically synonyms.
this is fun!!!
you are right again, matrces are for linear equations... (after looking up your link) so in this case this does no apply..
i said the quadratic equation is simpilfied because you just fill in the variables and you have your answers.. i don't mean to offend quadratic equation. it is a formula, and it does work... as with any formula, it gives you the correct answer after filling in the variables.. but it does not explain the steps needed to get your answers..
this really does makes me want to take up maths again... numbers are fun..lol
i can see some very clever ppl here in the hexus, and i am soooooo glad i'd joined..lol
you will be...(note my location, i'm not a physicist yet!)if you can answer this question.. :
is 0.999999999999 recurring
a) <1
b) =1
c) >1
any comments are welcome.. after all this is a community...Yeah that's right, I vaguely remember using algebra (and the aforementioned mysterious "i" to solve roots of negative numbers), but it's not really a big deal. I've never used matrices (dropped maths before that), but I've definitely factorised equations so I wouldn't worry about that.
Also, it's worth saying that the quadratic formula isn't really the best method because you're looking to factorise the equation, rather than solve it - although I admit that if you solve it you can probably factorise it fairly easily.
To be honest though, I never understood how to "complete the square" for some reason... I just used every other method going instead - so maybe I'm not the best person to be commenting
My guess is b) =1
The reason being is that there could be an infinite number of 9s after the decimal place meaning that it is essentially 1?
No, it's never 1. It's always <1.
It's convienient to think of it as equivalent to 1 sometimes, and you rely on that sometimes, as with approximations as it's approaching 1.
But what are these questions for?
There are currently 1 users browsing this thread. (0 members and 1 guests)
Posting Permissions
LinkBack URL
About LinkBacks
Reply With Quote
