Question

If x=2+under root 3 then find the value of x cube +1/xcube.

Answer 1

Answer:

52

Step-by-step explanation:

x=2+√3

x^3+1/x^3=?

1/x=1/2+√3

=2-√3

x+1/x=2+√3+2-√3

=4

x^3+1/x^3=(x+1/x)(x^2+1/x^2-1)

=4(x^2+1/x^2-1)

x^2+1/x^2=

x+1/x=4

squaring both sides

x^2+1/x^2+2=16

x^2+1/x^2=16-2=14

putting the value

4(14-1)

=4×13

=52