solving Quadratics help

[TideRower]

well there isnt an exact one (as far as i know) but there are many that can get arbitrarily close to them (and me being a physicist, that means exactly there)

There isn't an exact one, I've see/done the proofs. Obviously numerically it's quite easy (and stable) to get really close to the roots of the polynom.

But me being a mathematician the exact solution is not just close to it.

[LukaP]

There isn't an exact one, I've see/done the proofs. Obviously numerically it's quite easy (and stable) to get really close to the roots of the polynom.

But me being a mathematician the exact solution is not just close to it.

and we come to the classic physics-maths argument

 

oh and since this is lowlevel math, even if they had a powerN poly, the roots would be nice, so any numerical method would get you to a result

[PhilBoisvert]

oh, one more thing. factorising is stupid, once you realise there is a formula, and how to get it, because then, it translates to all the other higher power polinomials

You will see how factorising is NOT stupid when you get in the 3D stuff.

Once you get into sphere and the formula is all messed up, complete square is pretty much the only method you have to sort it out and find the origin of tge sphere and its radius. I have 3 math and 1 physic courses tgis semester in engeneering... Exam next week... Fml

[LukaP]

You will see how factorising is NOT stupid when you get in the 3D stuff. This one is easy, you have to use the conplete square method to solve the problem.

Once you get into sphere and the formula is all messed up, complete square is pretty much the only method you have to sort it out and find the origin of tge sphere and its radius. I have 3 math and 1 physic courses tgis semester in engeneering... Exam next week... Fml

mathematically, its the only logical way. for me, i would use some numerical method and get close enough to the result that the error is neglible compared to the inbuilt error in the task at hand

[Redliub]

ARGH! IT'S FACTORING, NOT FACTORISING DAMMIT! WTF!

[PhilBoisvert]

mathematically, its the only logical way. for me, i would use some numerical method and get close enough to the result that the error is neglible compared to the inbuilt error in the task at hand

Most of the time I use my TI Nspire (TI-84 is for kids )

[LukaP]

Most of the time I use my TI Nspire (TI-84 is for kids )

Mathematica for me

[HelloItsPersonalHD]

Use wolframalpha

https://www.wolframalpha.com/

[Biased Opinion]

I don't even remember how to solve quadratics with factorising.

[jameshumphries47]

ARGH! IT'S FACTORING, NOT FACTORISING DAMMIT! WTF!

sorry are you here to wind people up, go back to the hole you came for! and stop shouting

[LukaP]

sorry are you here to wind people up, go back to the hole you came for! and stop shouting

so was it all ok? did you explain to your teacher factorising is crapuseless in anyhting <pow5

[kingkickolas]

 

oh, one more thing. factorising is stupid, once you realise there is a formula, and how to get it, because then, it translates to all the other higher power polinomials

mathematically, its the only logical way. for me, i would use some numerical method and get close enough to the result that the error is neglible compared to the inbuilt error in the task at hand

 

I have to disagree, especially when it comes to solving quadratics (or higher polynomials) with variable entries.

For example in QM, when you often get these sorts of quadratics in exponents in integrals, where you have to complete the square a lot. Like this one I was just looking at

[PacMappy Solvalou]

It's those kinds of problems that read:

 

"Johnny has 2 apples and Alice has 3 oranges. Find the mass of the sun"

 

When all you had to do was: y = mx + b

 

[kingkickolas]

It's those kinds of problems that read:

 

"Johnny has 2 apples and Alice has 3 oranges. Find the mass of the sun"

 

When all you had to do was: y = mx + b

 

Yeah it's unfortunate that the pedagogy these days is to cram formulas into kids' brains instead of teaching them to actually think about problems and how to solve them.

[PacMappy Solvalou]

Even more disheartening is that more and more kids are being taught regurgitated stuff from the book, or in worse cases, stuff verbatim from the book without any filtering process to explain the oblivious main point of the lesson.

[kingkickolas]

Even more disheartening is that more and more kids are being taught regurgitated stuff from the book, or in worse cases, stuff verbatim from the book without any filtering process to explain the oblivious main point of the lesson.

 

Yeah I really wish students would read the book, and then get extra/clarifying information from the teacher.

It's better in college, but in my experience there are very few k-12 students who actually read their textbooks. I think teachers know this, and so they have to teach the kids the book information very dryly so that they at least get it once.

 

I could go on, but I think the biggest problem is that education -- and especially educators -- aren't as valued and respected in this country as they ought to be. (This is speaking from the States, mainly regarding pre-university.)

You get sayings like, "Those who can't do, teach." Which I think is just awful.

[Corvus]

I swear, looking at some of the other answers, I think they were trying to make it look so complicated you dropped out of school.

 

 

All you need to do is follow THIS and you will be OK kid !

 

-Picture of Complicated math stuff-

Is it bad that I recognize most of these?.. 

[TideRower]

Is it bad that I recognize most of these?.. 

Not at all, these are just trigonometric functions.

In my opinion the other way around would be worse (depending on age).

[LukaP]

Is it bad that I recognize most of these?.. 

this is still simple math i wish i had my physics notes with me that would be "bad" if you knew it all

[Pugs501]

this is still simple math i wish i had my physics notes with me that would be "bad" if you knew it all

Have you had Proofs yet?

[TideRower]

this is still simple math i wish i had my physics notes with me that would be "bad" if you knew it all

I've seen quite a few physics students having a hard time with math at university.

[LukaP]

Have you had Proofs yet?

thats maths that shit is just phylosophy now that we have learned the stuff we need for physics... 

 

i mean seriously, defining a function because it helps define another function. but to define that function, we define another functon that is the identity of the first function... what the hell

[LukaP]

I've seen quite a few physics students having a hard time with math at university.

idk, its not really complicated to me, just seems like stuff they should teach math students, and give me stuff that i can use, not philosocrap

[jameshumphries47]

so was it all ok? did you explain to your teacher factorising is crapuseless in anyhting <pow5

yeah i went and seen him he explained it i was like duuuuuh *facepalm* i believe maths should teach you the basics like taxes, mortgage repayments, and money managing!

in life how does defining a function help anyone in life. has Pythagoras therom  ever made anyone's life easier! NO!

[LukaP]

yeah i went and seen him he explained it i was like duuuuuh *facepalm* i believe maths should teach you the basics like taxes, mortgage repayments, and money managing!

in life how does defining a function help anyone in life. has Pythagoras therom  ever made anyone's life easier! NO!

it makes my life easier