Trialing the symbolic toolbox and attempting to run the 'Indefinite Integral of Univariate Expression' example from the int function documentation. Copy and pasting the exact code and recieve the following:
expr = -2*x/(1+x^2)^2;
F = int(expr)
Error using sym/subsindex (line 855)
Invalid indexing or function definition. Indexing must follow MATLAB indexing. Function arguments must be symbolic variables, and function body must be sym expression.
Is this a settings error? Demo/trial error? The symbolic differentiation tool works just fine. Many thanks for your help!