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Find the Morse's change of coordinates u = u(x, y) V = V ( 2, y) and ( u, v) ~ (x, y) as ( x, y) (0,0) that will bring to the sum of squares z = liu2 + 1202 the following function z = - x2 + 2 . y+ x2. arctan(x . y) + y sin(y) - 24 -25 Describe the largest possible domain in (x, y)-plane where this change of variables is valid