Matlab ignores pi in a function
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When I try to use:
syms x; y=3*cos(pi-x^2); diff(y)
it gives
6*x*sin(x^2)
it ignores the pi, giving an incorrect solution and I don't know how to solve it.
It also says that "y=-3*cos(x^2)", ignoring the pi again.
Thanks in advance.
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Image Analyst
2016-1-3
0 个投票
Why do you incorrectly think that cos(pi-theta) is not equal to -cos(theta)? It is. Just try plotting some angles on the unit circle to prove it to yourself. So you can use either equation because they are equivalent.
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