f(x,y,z)= x^2+ 3y^2+ 5z^2
k=x^2+ 3y^2+ 5z^2 if k=0 we have a ellipsewith with origin 0,0
when k>0 family of ellipses of one sheet
K<0 family of ellipses
I do not know if I am doing it right or if I am describing them exactly.
f(x,y,z)= x^2+ 3y^2+ 5z^2
k=x^2+ 3y^2+ 5z^2 if k=0 we have a ellipsewith with origin 0,0
when k>0 family of ellipses of one sheet
K<0 family of ellipses
I do not know if I am doing it right or if I am describing them exactly.