Question

please solve question

Answer 1

Hope it may help you!

The remained question:
x=1/2√3

Therefore, x^3 - 2x^2 - 7x + 5

= (1/2√3)^3 - 2(1/2√3)^2 - 7(1/2√3) + 5

= 1/24√3 - 2*1/12 - 7/2√3 + 5

= 1/24√3 - 1/6 - 7/2√3 + 5

=1/24√3 - 7/2√3 - 1/6 + 5

=(1 - 84)/24√3 + (-1+30)/6

=-83/24√3 + 29/6

= -83/24√3 * √3/√3 + 29/6

= -83√3/72 + 29/6

= 29/6 - 83√3/72