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You are not logged in. #1 20051213 03:31:22
average within intervalIf you want the average y value (height) of a igloo myrtilles fourmis #2 20051213 03:37:13
Re: average within intervalYou can divide by the class width before you integrate instead of afterwards, but that's pretty much the same thing. Other than that, I don't think there's a way. Why did the vector cross the road? It wanted to be normal. #3 20051213 05:49:36
Re: average within intervalI don't understand. So Oh you mean divide by 10 and factor out the before you do the integral? Last edited by John E. Franklin (20051213 05:52:31) igloo myrtilles fourmis #4 20051213 05:58:38
Re: average within intervalYes. So, in your example, that would be ∫ (x/10)dx. As I said, they're really just the same thing in a different order. Why did the vector cross the road? It wanted to be normal. #5 20051213 06:32:41
Re: average within intervalThanks, I got it. But that only works for y=constant? What I mean is so the 1/x is like dividing by the class width. But it doesn't work if it is another function because and then divide by class width. But this is different than the following where I divide by first: And clearly is not the same as . Sorry I left out the dx's in the equations; I don't understand what they are yet. I know it is an incremental piece of x, but I don't know where it is coming from. Does it appear when you decide to take the integral with respect to x? Last edited by John E. Franklin (20051213 06:39:59) igloo myrtilles fourmis #6 20051214 14:52:34
Re: average within intervalYou are getting a little confused with the notation. f(x)=x^2 is the same thing as y=x^2. f'(x) is the same as dy/dx=2x. Taking an integral is the exact opposite of taking an integral. An integral is also called an antiderivative. ∫dy = ∫2x dx is the same as y=x^2. #7 20051214 19:05:01
Re: average within interval["Taking an integral is the exact opposite of taking an integral"  you intended to say derivative for one of those, I think. If you want to, just edit your own post and I will delete this comment and it will all look really neat ] "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #8 20051215 03:48:19
Re: average within intervalYes, but it will still have the last edited by... bit so people will know that something's up. Plus, my post is here now. Why did the vector cross the road? It wanted to be normal. 