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23 votes
Can someone explain HOW to simplify this algebraic fraction, as in tell me why and what I need to do for each step : 1-n/n^2-1

User Sebastian Hernandez
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1 Answer

27 votes
27 votes

- I’m assuming the expression implies the following:

(1-n)/(n^2 - 1)

The steps goes as follows:

= -(n-1)/(n^2-1) (factored a negative out)
= -(n-1)/[(n+1)(n-1)] (Factored denominator into a difference of squares, but don’t just blindly accept the fact, expand it and you should get the original denominator)

At this point, the (n-1) terms cancel, as you should know: a real number, besides 0, over itself is 1.

= -1/(n+1) , which is the answer

Note: You could also see it as 1/-(n+1) or 1/(-n-1)
User Mohamedrias
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