Integrating sin(2x) in MATLAB

16 vues (au cours des 30 derniers jours)
Shane Yost
Shane Yost le 8 Juil 2013
Introduction:
I'm new to MATLAB and trying to learn how to integrate expressions.
Situation:
The expression to integrate is.....
sin(2x)
I'm entering the following code......
syms x
int(sin(2*x))
The answer MATLAB is displaying is.....
ans =
sin(x)^2
The answer I'm looking for is....... (-1/2)*cos(2x)+c

Réponse acceptée

Andrei Bobrov
Andrei Bobrov le 9 Juil 2013
syms x
out = feval(symengine,'combine',int(sin(2*x)),'sincos')

Plus de réponses (1)

Azzi Abdelmalek
Azzi Abdelmalek le 9 Juil 2013
(-1/2)*cos(2x)=(-1/2)*(cos^2(x)-sin^2(x))
=(-1/2)*(1-sin^2(x)-sin^2(x))
=(-1/2)+sin^2(x)
=sin^2(x)+c
The result found by Matlab and yours are the same
  1 commentaire
Jan
Jan le 9 Juil 2013
@Shane Yost: Interesting, isn't it? Matlab replied the correct result, but you've expected another correct result.

Connectez-vous pour commenter.

Catégories

En savoir plus sur Programming dans Help Center et File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by