Suppose we have a two-dimensional input space such that the input vector is x = [x1; x2]T . De ne the feature mapping (x) = [x21 ; p 2x1x2; x22 ; p 2x1; p 2x2; 1]T . What is the corresponding kernel function, i.e. k(x; z)? Do not leave () in your nal answer. Simplify your answer to write it using input vectors x; z and show your work