Suppose, for the sake of simplicity, that I need to compare two equivalent symbolic expressions in Matlab.

`syms a bx = sin(a + b);y = sin(a)*cos(b) + sin(b)*cos(a);`

And, obviously, we know that . Now if I use the Matlab functions isequal (or isequaln), I don't get the expected result, which is a logical 1, because this is an equality:

`>> isequal(x,y)ans = logical 0`

Why does it happen? Is there any function that does what I am trying to do?

Thanks!

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