MATLAB Need help in matlab is it possible to inverse a Matrix involve unknown?

[feicobain]

I need to find the transfer function a system equation and it is in the form

[x/y]=[A]^-1

x is input, y is out

[A] is a 2x2 matrix in the form of

A=[1+s 2
3 4+s ]

s is the laplace tranform function

Is it possible to output the inverse of [A] in MATLAB even it involve s?

I know I can inverse a 2x2 matrix by hand but I can't inverse a 4x4 matrix.

Cheers.

 

[MATLABdude]

As far as I know, not without the symbolic toolbox. Maple or Mathematica or Mathcad (or my old TI-89) can, however.