D = - 2x ^ 2 - y ^ 2 - 2xy + 4x + 2y + 2 - Dicamon

Question

D = - 2x ^ 2 - y ^ 2 - 2xy + 4x + 2y + 2

Answer

A - 2x ^ 2 - y ^ 2 - 2xy + yx + 2y + 5; =-8(x^ 2 +2xy+y^ 2 )+2(x+y)-x^ 2 +2x+5; =-(x+y)^ 2 +2(x+y)-1-(x^ 2 -2x+1) 1 - ((x - y) ^ 2 - 2(x + y) + 1] - (x - 1) ^ 2 + 7; =-(x-y-1)^ 2

Answer

ху 4x 2y A 1 +1 =-x(x^ 2 +2xy+y^ 2 )+2(x+y)x^ 2 +2c+5; =-(x+y)^ 2 +2(x+y)-1-(x^ 2 -2x+1)+5; =-[(x-y)^ 2 -2(x+y)+1]-(x-1)^ 2 +7 1 ( 1 v_i ^ (- - (x - y - 1) ^ 2) <= 0; - (x - 1) ^ 2

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