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Math Help - Help with problem

  1. #1
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    Help with problem

    We just started a new unit and the instructor hasnt explain how to do this even thoug i can tell its simple

    Find f '(a).
    f(x) = √(3x + 1 )
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  2. #2
    Super Member Matt Westwood's Avatar
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    f'(x) = \frac {3} {2 \sqrt {3x + 1}}
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  3. #3
    is up to his old tricks again! Jhevon's Avatar
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    Note that Matt's answer comes from writing the function as (3x + 1)^{\frac 12} and applying the chain rule

    the chain rule says: \frac d{dx}f(g(x)) = f'(g(x)) \cdot g'(x)

    here, f(x) = x^{\frac 12} and g(x) = 3x + 1
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