<PRE><B>Question 825192</B>
How to Factor the numerator and denominator of each expression completely?
(x^2+2x)/(x^2-4) and (x^2-5x+4)/(x^2-1)
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x^2 + 2x  is obvious
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x^2 - 4 is a difference of 2 squares
a^2 - b^2 = (a-b)*(a+b)
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x^2-5x+4 notice that 5 = 4+1
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x^2 - 1 another difference of 2 squares</PRE>