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Find the Morse's change of coordinates u = u(x, y) v = v( x, y) and ( u, v) ~ (x, y) as (a, y) (0, 0) that will bring to the sum of squares 2 = liu2 + 1202 the following function z = -x2+2.3 + x2. arctan(x . y) + y sin(y) - 24 - y Describe the largest possible domain in (x, y)-plane where this change of variables is valid