(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Differentiate

f(x) = 6-5x-x^{2}/ x^{2}-1

-------

A) -5-5x / x^{2}-1

B) 5 / (x+1)^{2}

C) -5-5x / (x^{2}-1)^{2}

D) -5 / (x+1)^{2}

E) -5+5x / x^{2}-1

F) None of the above

3. The attempt at a solution

(x^{2})(-5-2x)-(6-5x-x^{2})(2x) / (x^{2}-1)^{2}

Simplified to:

5x^{2}-10x+5 / x^{4}-2x^{2}+1

But it's not one of the answer choices. I tried simplifying it even further to:

5(x^{2}-2x) / x^{4}-2x^{2}+1

or

5(x^{2}-2x) / (x^{2}-1)^{2}

But I can't see where else to go with it.

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# Homework Help: Find derivative using Quotient rule

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