Can you minimize a function in MATLAB?

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Elise M.
Elise M. on 29 Apr 2015
Commented: the cyclist on 29 Apr 2015
The force is F=(mMg)/(cos(theta)+Msin(theta), and theta is between 0 and pi/2 I have the values for m, M and g but I need to find the angle that the force is the smallest. I also need to find the magnitude of the force. To find the angle where force is the smallest, do I need to minimize it? How would I go about doing that?
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John D'Errico
John D'Errico on 29 Apr 2015
Edited: John D'Errico on 29 Apr 2015
It depends on what M means. If M has units, then, yes, there is arguably a problem, because we would have
cos(theta) + M*sin(theta)
in an additive expression. That works only if M is unit-less.
But to be honest, it looks like M might be unit-less. My guess is m is a mass, g looks like an acceleration. Therefore m*g is a force, and we have no use for units on M.
the cyclist
the cyclist on 29 Apr 2015
You are absolutely correct. I assumed that M is a large mass, and m a small mass.

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Answers (2)

the cyclist
the cyclist on 29 Apr 2015
Yes, you can use the fminbnd function.

John D'Errico
John D'Errico on 29 Apr 2015
Use fminbnd. I'll show you how to define the function.
F = @(theta) (m*M*g)./(cos(theta)+M*sin(theta));

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