Answer:
3
Step-by-step explanation:
x= 1/ (2-√3),
Rationalising denominator,
x= 1/(2-√3) *(2+√3)/(2+√3)
x= (2+√3) /22 -(√3)2 = (2+√3) /4-3= (2+√3)
Substituting value of x =(2+√3) in
x3 -2x2 -7x +5, we get
(2+√3)3 -2(2+√3)2 -7(2+√3) +5
= 8 +12√3+18+3√3- 8-8√3-6-14-7√3+5
=3
