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kashiark
Jun21-09, 12:54 PM
Wolframalpha.com is a really good one. It looks like a search engine, and to find the derivative, type in d/dx(function.) To do antiderivatives, you need the symbol ∫. For limits use lim(function) as x->whatever.

thrill3rnit3
Jun21-09, 01:05 PM
I found some errors in it doing simple antiderivates.

qntty
Jun21-09, 04:34 PM
For antiderivatives you can just type "antidifferentiate f(x) dx" or "integrate f(x) dx"

Theorem.
Jun27-10, 02:01 PM
Wolfram is generally reliable, Although it often generates solutions that have been simplified in a very strange manner. I find it to be a useful for double checking my work. For indefinite integrals, possible solution pathways are also provided. If you get a question wrong, these usually help pinpoint the problem, Although I'd never completely rely on it. I have always considered it a supplementary tool I can use to verify my knowledge and confidence, nothing else.

phyzguy
Jun27-10, 02:06 PM
I found some errors in it doing simple antiderivates.

I have sometimes thought it was making an error, but it has always turned out to be either my error or my misunderstanding of the result returned. Do you have specific examples where it made an error?

Theorem.
Jun27-10, 02:29 PM
I have sometimes thought it was making an error, but it has always turned out to be either my error or my misunderstanding of the result returned. Do you have specific examples where it made an error?

I have had the same problem (not errors, but "thinking" the wolfram computation was wrong). I have noticed that with lots of trigonometric and some more advanced integrals, wolfram has a tendency to perform odd simplifications that usually throw me off, but that are in fact correct (just not necessary so simple).

Leptos
Jun27-10, 07:48 PM
I found some errors in it doing simple antiderivates.
I haven't had this problem, do you have any examples of when it makes these supposed errors?

thrill3rnit3
Jun27-10, 08:53 PM
I haven't had this problem, do you have any examples of when it makes these supposed errors?

I posted my comment over a year ago, so they have probably fixed the error(s) by now.

either way I don't remember exactly the problem(s), but yeah I did find some error(s).

tayyaba_azim
Jul13-10, 10:27 AM
I've just checked this calculator for the partial differentiation of ((x1-m1)^2/s^2) w.r.t 'm' i.e. d/dm(((x1-m1)^2/s^2))

and the result was

(-2 (-m1 + x1)^2 s'[m])/s^3 + (2 (-m1 + x1) (-m1'[m] + x1'[m]))/s^2;

I'm still confused how do we differentiate a function containing 'm1' w.r.t 'm'; m is a 2D variable which consists of (m1,m2).
Can please somebody explain this to me. I'll be really very grateful.

phyzguy
Jul14-10, 07:10 AM
Wolfram alpha doesn't know that m is a 2d variable consisting of (m1,m2). SInce you differentiated an expression by m, and the expression doesn't contain m (only x1, s, and m1), it assumes that all three of x1, m1, and s are functions of m, and gives you the derivative using that assumption.

tayyaba_azim
Jul14-10, 07:46 AM
Thank you very much for your reply. Can u tell me how to solve my equation in general or through the calculator?

phyzguy
Jul14-10, 04:35 PM
It depends what you are trying to do. You might want to read up on vector calculus - I suggest starting with:
http://en.wikipedia.org/wiki/Vector_calculus
Do you want the gradient of the scalar function f=((x1-m1)^2/s^2) ? In this case, since f is independent of m2, it would just be df/dm1*e1, where e1 is the unit vector in the m1 direction. What problem are you trying to solve exactly?