Uprościć wyrażenie 2(x-y)(x+y)-3(x+2y)^2+(x-y)^2 a następnie oblicz jego wartość dla x=pierwiastek 2 i y = pierwiastek 2 dzielone na 2

[latex]2(x-y)(x+y) - 3(x+2y)^{2} + (x-y)^{2}[/latex] [latex]x = sqrt{2}[/latex] [latex]y = frac{sqrt{2}}{2}[/latex] [latex]2(x^{2} - y^{2}) - 3(x^{2} + 4xy + 4y^{2}) + x^{2} - 2xy + y^{2} =[/latex] [latex]2x^{2} - 2y^{2} - 3x^{2} - 12xy -12y^{2} + x^{2} - 2xy + y^{2} =[/latex] [latex]2x^{2} - 3x^{2} + x^{2} - 2y^{2} - 12y^{2} + y^{2} - 12xy - 2xy =[/latex] [latex]3x^{2} - 3x^{2} + y^{2} - 14y^{2} - 14xy =[/latex] [latex]-13y^{2} - 14xy[/latex] [latex]-13frac{sqrt{2}}{2}^{2} - 14sqrt{2}frac{sqrt{2}}{2} = -13frac{2}{4} - 14 = frac{-13}{2} - 14 = frac{-13 - 28}{2} = frac{-41}{2} = -20,5[/latex]