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    2) Find the values of x which for f(x) is a decreasing function given that f(x) equals:

    F) x+25/x
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    (Original post by Guccigirl)
    2) Find the values of x which for f(x) is a decreasing function given that f(x) equals:

    F) x+25/x
    Are you asking:

    When is f(x) = x + (25/x) a decreasing function?

    What have you done so far?
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    (Original post by Guccigirl)
    2) Find the values of x which for f(x) is a decreasing function given that f(x) equals:

    F) x+25/x
    If f(x) is a decreasing function f'(x)<0

    Differentiate the equation and then solve the inequality
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    (Original post by Lunch_Box)
    Are you asking:

    When is f(x) = x + (25/x) a decreasing function?

    What have you done so far?
    i have differentiated it so I got


    f'(x)=1-25/x^2
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    (Original post by Guccigirl)
    i have differentiated it
    Then read what Robbie242 has posted
 
 
 
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