# Why does Mathematica give an incorrect answer to this multiple integral?

Check our answers to ‘Why does Mathematica give an incorrect answer to this multiple integral?’ - we found 55 replies and comments relevant to this matter. The best answers are submitted by users of Mathematica, Yahoo! Answers and Answerbag.com.

## Best solution

• ### Why does Mathematica give the wrong answer when integrating?

I integrate Integrate[Exp[I Cos[b - c]] Cos[b], {b, 0, 2 Pi}] Mathematica gives: 2 I Pi BesselJ[1, 1] Which is indepedent on $c$. However, the result is NOT independent on $c$. The numerical value of what Mathematica gives is 0. + 2.76492 I while NIntegrate[Exp[I Cos[b - 0.5]] Cos[b], {b, 0, 2 Pi}] Gives 1.16655*10^-10 + 2.42645 I Certainly not the same. If we multiply the value Mathematica gives with $\cos(0.5)$ the result is the same. What is wrong?

Looks like a bug that ran off in the development version of Mathematica. In[1]:= Integrate[Exp[I Cos...

## Other solutions

• ### How do I graph P' = kP(1 - P/N)(P/T - 1) - a (where k, N, and T are constants) in Mathematica or Matlab?

If you're going to give me an answer on how to graph in Mathematica then it'd be preferable if you told me how to do this using the StreamPlot command. Thanks.

which is the independent variable?

• ### Why is it when you give an honest answer on sites your answer is reported and removed?

When I give an honest answer on this site or any site where people ask a question my answer is reported and removed? Why is that? What is the point in someone asking a question if they don't want the truth? That is wrong. As long as you give someone...

Not progressive liberal enough

• ### Why ppl cant give a straight answer?

This is the deal Many people that have been in my life, whether they are a friend or acquaintance cant give you a straight answer. They beat about the bush and they PROPOSE certain endevours for the future to happen. Then what happens> there is nothing...

You have to meet certain people for that5 type of mentality. Most people can't do the simplest things...

• ### Why don't many people who answer "crime questions" give a direct answer to the question?

For those of you who don't know, it is quite common on YahooAnswers (and even real life situations) for people who are in legal trouble (or think they are in legal trouble) to post questions on like "What should I do?" or "Can the law...

• ### Give me a good reason why i should give u the best answer.?

Lie,say the truth beacause i do not care just tell me why u should get the best answer i want to see why one person should get the best answer from this dumb question. Compiment me say nice things to me or about what u do that makes the world a better...

Because you get three points back for choosing a best answer and I just informed you of that. And also...

• ### If a funny answer makes you burst out laughing, do you give it best answer even if it's incorrect?

I give more points for wit than accuracy.

Pretty much, taking this seriously is not worth it. i usually give best to people who try to insult...

• ### Why 14 club rule in golf can you give me one logical answer why it can't be 16?

If you say then why not 50 clubs ''Rules are there to protect you"" Garbage I wil automatically give you thumbs down give me a logical answer.

Because if you "stick" one more "club" in a "bag"...you get in trouble...

• ### Why does he give me short answers? 10 points to best answer? HELP!!?

So I have this friend. He's been flirting with me a lot lately, which made me think he likes me, he called me honey, darling, and sends winks. We used to talk everyday. But lately he changed. We changed. Everything changed! We still talk everyday, he...