Quadratic modular equation?

So I have a bit of an issue. I have a matrix with coefficients on top and powers of x on bottom (e.g. var = [3 4, 2 1]; where the corresponding equation is f(x) = 3x^2 + 4x) The code is set up to allow the user to enter a matrix of any length with 2 rows. I need to integrate whatever function they input in this format. How do I make a function that will change depending on what they enter?

Answer 1

[madhan ravi]

var = input('enter 2 by 2 matrix');
f = @(x) input('enter equation like 3*x.^2 + 4*x for example')
f(var)

Like this?