Well get to it. If you are very new to matlab then have a look at On-ramp material - which should have you up and running faster than you can expect answers here to do. If you already have looked at that, then I suggest you look up the help and documentation of meshgrid, pcolor and after doing that you should be able to write a matlab-function that calculates the given function and understand one way of plotting it for some sensible choise of x and y.
HTH
