Question

PLZZZZ PLEASE SOLVE THIS QUESTION, I WILL MARK YOU BRAINLIEST + 5 STAR + THANKS.
( 25+ PTS QUESTION )

Answer 1

x=1/2-√3
rationalising it,
x=1/2-√3*2+√3/2+√3
x=2+√3

x^3 - 2x^2 - 7x +5
= (2 + √3)^3 - 2(2 + √3)^2 - 7(2 + √3) + 5
= (2 + √3) [(2 + √3)^2 - 2(2 + √3) - 7] + 5
= (2 + √3) [4 + 3 + 4√3 - 4 - 2√3 - 7] + 5
= (2 + √3) [-4 + 2√3] + 5
= -2(2 + √3)(2 - √3) + 5
= -2(1) + 5
= 3

Hope it helps u...
if yes, mark brainliest...
have a gr8 day ahead...

@TeraBhalaHo

Answer 2

x^3 - 2x^2 - 7x +5= (2 + √3)^3 - 2(2 + √3)^2 - 7(2 + √3) + 5= (2 + √3) [(2 + √3)^2 - 2(2 + √3) - 7] + 5= (2 + √3) [4 + 3 + 4√3 - 4 - 2√3 - 7] + 5= (2 + √3) [4 + 2√3] + 5= 2(2 + √3)(2 - √3) + 5= 2+ 5= 7

AM I right ?