Pilnie potrzebne ! Oblicz wartość wyrażenia : (2x-y)^2 - 2(2x-y)(x+2y)+(x+2y)^2 dla x = √5 - 6 i y=√3-2

[latex](2x-y)^2 - 2(2x-y)(x+2y)+(x+2y)^2 =\\=4x^2-4xy+y^2-2(2x^2+4xy-xy-2y^2) +x^2+4xy+4y^2=\\= 4x^2-4xy+y^2-4x^2-8xy+2xy+4y^2 +x^2+4xy+4y^2=\\= x^2 -6xy+9y^2 \\ x = sqrt{5} - 6 i y= sqrt{3}-2[/latex] [latex](sqrt{5}-6)^2 -6 ( sqrt{5} - 6 )(sqrt{3}-2)+9 (sqrt{3}-2)^2 =\\=5-12sqrt{5}+36-6(sqrt{15}-2sqrt{5}-6sqrt{3}+12)+9(3-4sqrt{3}+4) =\\=5-12sqrt{5}+36-6 sqrt{15}+12sqrt{5}+36sqrt{3}-72+27-36sqrt{3}+36=\\=32 -6 sqrt{15}[/latex]