Question

if x = 3+√5/2 find x+1/x also find x^3+1x^3

Answer 1

X=1/2(3+v5)

1/x=1/2(3-v5)

X+1/x=3

x^2 +1/x^2 =(x+1/x)^2 - 2=7

X^3 +1/x^3 =(x+1/x)^3 - 3((x+1/x)

=27-9=18