Can you find y^3?

Algebra Level 2

If $y+\dfrac{1}{y}=1$ , then value of $y^3$ is?

1 2 -1 3 0

1 solution

Ravi Dwivedi
Nov 6, 2015

$y+\frac{1}{y} =1$

$y^2 -y+1=0. \quad (1)$

$y^2=y-1$

Multiply both sides by $y$ we get

$y^3=y^2-y =\boxed{-1}$ (using equation $(1)$