[MOVED] Least Common Denominator for rat'l expressions

[sallyk57]

Please help with this question. Thanks

Find the Least Common Denominator of:

1/(x^2 +x ), 1/(x^2 - 1), and 1/(x^3 - x)

the choices are...

a)x^3 + 2x^2 - 1
b)x^7 - 1
c)(x^2 + x)(x^2 - 1)(x^3 - x)
d)x(x + 1)(x - 1)

 

[pka]

\(\displaystyle \begin{array}{rcl}
\frac{1}{{x^2 + x}} & = & \frac{1}{{x\left( {x + 1} \right)}} \\
\frac{1}{{x^2 - x}} & = & \frac{1}{{\left( {x + 1} \right)\left( {x - 1} \right)}} \\
\frac{1}{{x^3 - x}} & = & \frac{1}{{x\left( {x + 1} \right)\left( {x - 1} \right)}} \\
\end{array}\)
What is the LCD?