If f is a function of two variables, we define the graph of (r, y) in ryz-space f(r, y). In general, such a graph will be a surface in to be the graph of the equation z = 3-space. E Xample: f x ,y) = Jx +y?-I %3D 2. =2 =Jy? +y? -1 =S3 * 53 2; x+ y2 -1 (Hyperboloid of 1-sheet) =o*+y - | =o =3 x*+y2= 4 Ccirele r=2) Example: f( X,y) = x + y? r=1 a = x? +y? (paraboloid) 1 = x Z =0 pointlo,o, 0) =| + x + y = 1 %3D 1 Question. f(X)%=Jx?+ y2 1. 2. 2.