Question 454771
3a^2/a^2+a+1 2a/a-1 a^3/a^3-1 
-----
Factor each denominator:
a^2+a+1 is not further factorable.
a-1 is not further factorable.
a^3-1 = (a-1)(a^2+a+1)
-------------------------
LCD = (a-1)(a^2+a+1)
====================
Cheers,
Stan H.