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anonymous
 one year ago
find the derivative of f(x) = 3/x at x=4
anonymous
 one year ago
find the derivative of f(x) = 3/x at x=4

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I got 3/4 but im not sure if that is correct?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0did you find the derivative of f(x)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0How would you do that? Would it be dw:1434601306329:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0no, not quite. You are finding the derivative by using the definition of a derivative. Have you learned the short hand way of finding derivatives by using the the derivative rules?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Would you do the power rule?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0You would use the quotient rule

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I dont know what that is

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1434601640378:dw ring a bell?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0if it does not that is fine, we can work with the definition of a derivative.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1434601759504:dw is where you would begin.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0oh i just forgot to put it over h

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0then get the numerators to a common denominator

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ok so you get (3/x^2+xh  3/x^2+xh) / h

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0which becomes (6/x^2+xh ) / h ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0you forgot to multiply the top by what the value with which you multiplied the bottom

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0at the last step, you were supposed to get ((3x/x^2+xh)(3(x+h)/x^2+xh))/h

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1434602235743:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Use L'Hopital's Rule to find derivative, then plug in 4. L'Hopital's Rule: (denominator * derivative of top) (numerator * derivative of bottom)/(denominator^2) Derivative of 3/x= 3/x^2 Plug in (4) = 3/16

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1434602370201:dw dw:1434602394506:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1434602511993:dw If you simplified everything correctly you should get

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0now you have to cancel out the h and evaluate the limit to find your derivative, or did you use the other guy's method?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0elysecollinsm=other guy
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