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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?

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1did 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

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1no, 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?

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1You would use the quotient rule

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

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1dw:1434601640378:dw ring a bell?

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1if it does not that is fine, we can work with the definition of a derivative.

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1dw: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

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1then 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 ?

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1you forgot to multiply the top by what the value with which you multiplied the bottom

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1at 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.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

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1dw:1434602511993:dw If you simplified everything correctly you should get

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1now you have to cancel out the h and evaluate the limit to find your derivative, or did you use the other guy's method?

dessyj1
 one year ago
Best ResponseYou've already chosen the best response.1elysecollinsm=other guy
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