Give the first and second derivative of the function f(x) = 5/x - 9x + 4

  1. Re-write f(x) as f(x) = 5x^(-1) - 9x + 42) Find first derivative as usual - multiply each term by it's power and subtract 1 from the power:f'(x) = (-1)(5x^(-2)) - (1)(9)Simplify to get f'(x) = -5/x^(2) - 9Find second derivative using the same method:f'(x) = -5x^(-2) - 9f''(x) = (-2)(-5x^(-3))f''(x) = 10/x^(3)
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Answered by Harvey B. Maths tutor

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