Question

Sendo X=√2+3√5 e Y= 3√5 -2. Determine: X+Y e X - Y

Answer 1

$x = \sqrt{2} + 3\sqrt{5}\\ y = 3\sqrt{5} -2\\x + y = \sqrt{2} + 3\sqrt{5} + 3\sqrt{5} -2 = 6\sqrt{5} + \sqrt{2} - 2 \\x - y = \sqrt{2} + 3\sqrt{5} - (3\sqrt{5} -2) = \sqrt{2} + 3\sqrt{5} - 3\sqrt{5} + 2 = \sqrt{2} + 2$