Question

Aflati x patrat +y patrat,știind ca x-y =2√3 si xy=9

Answer 1

   
[tex](x-y)^2 = x^2 - 2xy + y^2 \\ \\ (x-y)^2 = x^2+ y^2 - 2xy \\ \\ x^2+ y^2 = (x-y)^2 + 2xy \\ \\ x^2+ y^2 = (2 \sqrt{3} )^2 + 2\cdot 9 = 4\cdot 3 + 2\cdot 9 = 12+18=\boxed{30}[/tex]