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Math Help - Derivative of this function?

  1. #1
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    Derivative of this function?

    I got:

    1/2t^(-1/2)(x+14) + SQRT of x.

    why is this wrong?
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  2. #2
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    I don't know why your derivative has a t in it.

    y = x^{\frac{1}{2}}(x+14).


    \frac{dy}{dx} = x^{\frac{1}{2}}\,\frac{d}{dx}(x + 14) + (x + 14)\,\frac{d}{dx}(x^{\frac{1}{2}})

     = x^{\frac{1}{2}} + \frac{1}{2}(x + 14)x^{-\frac{1}{2}}

     = \sqrt{x} + \frac{x + 14}{2\sqrt{x}}.
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  3. #3
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    WOWWWWWWW. That was the problem. I inserted a 't' instead of 'x'. I am a smart one obviously.
    Thank you.
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