>> syms x n;

f=x^n;

int(f)

ans =

x^(n+1)(n+1)

??? Undefined function or method 'syms' for input arguments of type 'char'.

>> syms 'x''n';

f=x^n;

int(f)

ans =

x^(n+1)(n+1)

??? Undefined function or method 'syms' for input arguments of type 'char'.

>> char 'x''n';

f=x^n;

int(f)

ans =

x^(n+1)(n+1)

??? Undefined function or variable 'x'.