SOLUTION: if x+1/x= 2 find the value of 8x^3+1/x^3

Algebra.Com
Question 667681: if x+1/x= 2 find the value of 8x^3+1/x^3
Answer by lwsshak3(11628)   (Show Source): You can put this solution on YOUR website!
if x+1/x= 2 find the value of 8x^3+1/x^3
..
x+1/x= 2
x^2+1=2x
x^2-2x+1=0
(x-1)^2=0
x-1=0
x=1
..
8x^3+1/x^3
=8+1
=9

RELATED QUESTIONS

If x^2 + 1/x^2 =102, find the value of x^3 -... (answered by rothauserc,ikleyn)
if x=1+sqrt2+sqrt3,then find the value of... (answered by ewatrrr)
If f(x) = 8x^3 + 5x^2 - x + C and f(-3) = 1, what is the value of C? (answered by jim_thompson5910,josmiceli)
If f(x) = 8x^3+5x^2-x+C and f(-3)=1, what is the value of... (answered by lynnlo)
If f(x) = 8x^3+5x^2-x+C and f(-3)+1, what is the value of... (answered by lynnlo)
if (x-(1/x))=3 find the value of... (answered by ramkikk66)
if x+1/x=3 then find the value of... (answered by ikleyn)
If x=1/2 is a zero of the polynomial f(x)=8x^3+ax^2-4x+2, find the value of... (answered by stanbon)
if x=sqrt{3+2sqrt(2)} then find the value of x^2+1/x^2 and... (answered by mananth)