bah my math book is horrible!!

[dpopiz]

^

 

[Syringer]

Post a problem and one of us can help walk you through it..

 

[BigJ]

If I could explain differential equations to you that easily, I'd be in a college somewhere as a professor doing it.

Anything else you need explained while we're at it? Maybe linear algebra? Or Multi-variable calculus?

 

[dpopiz]

well, I guess I just don't understand the concept...
my math book says it's just "and equation involving two derivatives of a function"


here's a problem; hopefully something will click in my head if you can show me how to solve it:


(dy/dx) = [f(x)/f(y)]

 

[brxndxn]

Differential equations...

1. Start with something simple.
2. Extrapolate it to make it more complicated in a general sense.
3. Extrapolate it to make it more complicated in a detailed sense.
4. Add both senses together.
5. Make sure it takes up a whole page.
6. Answer will be missing something and you get 4/5 credit.

 

[Semidevil]

Originally posted by: dpopiz
well, I guess I just don't understand the concept...
my math book says it's just "and equation involving two derivatives of a function"


here's a problem; hopefully something will click in my head if you can show me how to solve it:


(dy/dx) = [f(x)/f(y)]

basically, given an equation, take the anti-derivative of both sides, and get it in terms of y = ???

 

[MrLuckyPants]

Drop Differential Equations and take Home Economics instead. You'll be the only guy there -- think about it...

 

[Justin218]

math profs need to give more partial credit

 

[chuckywang]

I know differential equations.

f(x) dx = f(y) dy, so just integrate both sides. Don't forget about the constant of integration.

 

[DrPizza]

Uh, you've gotta be kidding, right?!
You want us to convey to you multiple texts worth of information in just a couple of posts?!

 

[Random Variable]

So I guess that means you wouldn't know how to solve a differential equation by using Laplace transforms.

 

[Orsorum]

Originally posted by: brxndxn
Differential equations...

1. Start with something simple.
2. Extrapolate it to make it more complicated in a general sense.
3. Extrapolate it to make it more complicated in a detailed sense.
4. Add both senses together.
5. Make sure it takes up a whole page.
6. Answer will be missing something and you get 4/5 credit.

That's how I survived it!

 

[ConwayJim]

this is calculus right?

 

[Darien]

Originally posted by: dpopiz
well, I guess I just don't understand the concept...
my math book says it's just "and equation involving two derivatives of a function"


here's a problem; hopefully something will click in my head if you can show me how to solve it:


(dy/dx) = [f(x)/f(y)]

That's pretty much it. It doesn't need two derivates to be a diffeq though.

eg: F = m^-1 * d^2x /dt^2, though it could be pointed out that it is the 2nd derivative of position. (So if yo udon't like this example, integrate both sides to get an expression for velocity)

 

[JohnCU]

y' = ty

doesn't get much simpler than that, and my differential equations book sucks. all the answers in it are wrong.

 

[Trevelyan]

This guy makes really good summaries for Calc and Diff Eq:

http://tutorial.math.lamar.edu...Browsers/3401/3401.asp