In order to solve a multivariate non-linear least squares problem, you need to define input 'x' as a matrix, where each row corresponds to an
independent variable. However, since you can only pass a vector, you would
need to first reshape the matrix into a vector and reshape it back into a matrix
in the function.
Hence a modification of the code will be as follows:
function F = myfun(x)
% reshape x back to a matirx
k = 1:10;
F = 2 + 2*k-exp(k*x(1))-exp(k*x(2));
