Plotting a saddle at given points?

I have a function f(x,y) = (Polynomials of x and y)

I solved this on paper and found that I have saddle points at (1,3)

I am wondering how I can plot this on matlab?

I attempted to use fplot and since my function has x and y (two variables ) it didnt work.

I also tried the basic meshplot of a saddle but I couldnt get my points to be incorperated in the graph.

Thanks

Answer 1

[Star Strider]

‘I attempted to use fplot and since my function has x and y (two variables ) it didnt work.’

Use fsurf instead.