Derivative Question.

If f(x)= −5x^5−3x^4−7x^3

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x^4

find f′(x).

### 1 Answer | Add Yours

`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`

### 1 Reply | Hide Replies ▲

Thank you very very much.

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