Question 2139: Can this be factored and what are the factors?
__3
X - 1 (thats X cubed minus 1)
Thanks
david r.
Found 2 solutions by sehar, longjonsilver:
Answer by sehar(13)   (Show Source):
Answer by longjonsilver(2297)  (Show Source):
You can put this solution on YOUR website! if you need to find factors of a polynomial, then the factor theorem is the place to start...it can be tedious, but tough :-).
You look for a value (a number) that when you put into the polynomial, you get zero...start with +1, then try -1 then +2 etc...
if x was 1...(1)^3 -1 is indeed zero, so (x-1) is a factor of te polynomial.
To find the other factor, you have to divide your answer into the original. To visualise what we have done so far, an example helps...the question has given you a number, say 27 and asked you to factorise it, ie write it as 2 numbers multiplied together. The first factor is found by trial and error...try 2...nope...try 3...yes. So to find the other number (here, 9) we say "what is 27 divided by 3"?
likewise...what is  divided by (x-1)? Use long division and i think the answer is x^2+x+1. These are factors, so leave it at that.
jon
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