Question

if x=(2+√5)^1/2 + (2-√5)^1/2
y=(2+√5)^1/2 - (2-√5)^1)2
evaluate x^2+y^2​

Answer 1

Answer:

X=(2+✓5)½+(2-✓5)½

X=½{(2+✓5)+(2-✓5)} (taking ½ as common)

X=(½)(2+2)

X=½(4). =2

y=(2+✓5)½-(2-✓5)½

y=½(2+✓5-2✓5) (taking ½ as common)

y=½(2✓5)=✓5

x^2+y^2=(2)^2+(✓5)^2

=4+5 =9