Discussion Forum

If $x = 1 + \sqrt{2}$ and $y = 1-\sqrt{2}$, find the value of $(x^{2}+y^{2}).$

Answer:

Explanation:

$(x^{2}+y^{2}) = (1 +\sqrt{2}) + (1 -(\sqrt{2}  ^{2})$
$= 2 [1^{2} + \sqrt{2}  ^{2}] = 2\times 3 = 6.$