Error using / Arguments must be numeric, char, or logical. what should I do I tried but did not seem to work?

>> m=2+0

m =

2

>> n=2+5

n =

7

>> syms x

>> f=inline(2*x^2-(3*m-n)*x-m*n)/(x^2+(m-n)*x-n*m)

Error using /

Arguments must be numeric, char, or logical.

Answer 1

[Chandler Hall]

To create a symbolic function, you must first declare it via the syms function, and then define its content. The syntax for this is straightforward but atypical:

m = 2; n = 7;
syms f(x) 
f(x) = (2*x^2-(3*m-n)*x-m*n)/(x^2+(m-n)*x-n*m);

[Walter Roberson]

This is not correct. You can create a symbolic function in three different ways:

syms Name(Variable list)
Name(Variable list) = symbolic expression
Name = symfun(symbolic expression, Variable list)

The syms form has the side effect of defining the variables, but is not required before either of the other approaches.

Answer 2

[Walter Roberson]

Never inline() a symbolic expression, it is not defined. matlabFunction() instead.

Never eval() a symbolic expression either, use subs()