The example below indicates my problem. In the first case, matlab cannot integrate the function provided to it and simply returns the computation I asked it to evaluate. In the second case, matlab is successful and returns a symbolic expression. The output argument of both `int` computations is of class `sym`, but, obviously, one is useful while the other is not. I could, of course, distinguish between them by searching for the string `int` in `char(Ans)` but that's a pretty inelegant thing to do.
f = @(x)((x+10)*exp(-x)/(sqrt(x*x+20*x)));
Ans= int((exp(-x)*(x + 10))/(x^2 + 20*x)^(1/2), x, 0, 1)
Ans = int(x^2,x,0,b)