Question

if x is 2+root 5, what is x+1/x the whole square

Answer 1

Answer:

1

Step-by-step explanation:

x+1/x= 2+root 5+1/2+root5

multiply both sides with 2-root5

=(2+root5)(2-root 5) / (2+root5)(2-root 5)

it is in form of (a+b)(a-b) so we get a^2-b^2

=(2^2 -(root 5)^2) / (2^2- (root 5)^2)

both numerator and denominator get called and we get 1

=1

therefore,

x+1/x= 1