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Derivative Question.  If f(x)= −5x^5−3x^4−7x^3            ...

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xfaceless | Student, Undergraduate | eNoter

Posted October 2, 2013 at 10:33 AM via web

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Derivative Question. 

If f(x)= −5x^5−3x^4−7x^3

            ---------------------

                    x^4

find f′(x). 

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aruv | High School Teacher | Valedictorian

Posted October 2, 2013 at 10:41 AM (Answer #1)

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`f(x)=(-5x^5-3x^4-7x^3)/x^4`

`=(-x^3(5x^2+3x+7))/x^4`

`=-(5x^2+3x+7)x^3xxx^(-4)`

`=-(5x^2+3x+7)x^(-1)`

`=-5x-3-7x^(-1)`

`Thus`

`f'(x)=-5-7(-1)x^(-2)`

`=-5+7/x^2`

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xfaceless | Student , Undergraduate | eNoter

Posted October 2, 2013 at 11:34 AM (Reply #1)

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Thank you very very much. 

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