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Boobs aren't Puppies or Jugs
Lv 7
Boobs aren't Puppies or Jugs asked in Science & MathematicsMathematics · 8 years ago

Please help me with Calculus?

For what value of k will x+k/x have a relative maximum at x=-2?

A) -4

B) - 2

C) 2

D) 4

E) None of these.

Update:

@Captain Matticus - It's x+(k/x)

3 Answers

Relevance
  • osama
    8 years ago
    Favorite Answer

    K = 4

    I think mark is right

  • Anonymous
    8 years ago

    I will assume:

    f(x) = x + k/x

    f'(x) = 1 - k/x² = (x² - k)/x² = 0

    x² = k

    when x = -2, k = 4

    f''(x) = 2k/x³ < 0, so we require k = 4.

  • Captain Matticus, LandPiratesInc
    Lv 7
    8 years ago

    Is it (x + k) / x or x + (k/x)?

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