Question

if x=3+√8, find x²+1/x²​

Answer 1

Answer:

x^2= 9 + 8= 17

1/x^2 = 1/ 17

17 + 1/17 = 289+1/ 17

= 290/ 17

= 17.05

Answer 2

Answer:

x=3+root8

x=3+root8 (3-root 8)/(3 -root 8)

x=(9-8)/(3-root8)

x=1/(3-root8)

Or we can write 1/x =(3-root8)

Put the value and find out

=x^2+(1/x)^2 so, x^2+(1/x)^2=(3+root 8)^2 + (3-root8)^3

=9+6root8+9-6root8 +8

=34 ans