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Math Help - derivative of an exponential e

  1. #1
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    derivative of an exponential e

    Little help please, my answer doesn't check out. need to find the derivative


    Problem is e to x-1 / 3x2 -4

    thats e to the x-1, divided by 3x squared - 4

    I got -6xe to the x-1 divided by 3x squared - 4

    (how do you write exponents on this forum)
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  2. #2
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    \frac{d}{dx} (e^u) = e^u \cdot \frac{du}{dx}

    where u = \frac{x-1}{3x^2 - 4}

    can you find \frac{du}{dx} ?
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  3. #3
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    minus 6x squared minus 6x - 4 / (3x squared -4)squared, but what happened to the E?
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  4. #4
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    oppps meant minus 3xsquared -6x-4
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  5. #5
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    \frac{d}{dx} \left[\frac{x-1}{3x^2-4}\right]

    \frac{(3x^2-4)(1) - (x-1)(6x)}{(3x^2-4)^2}<br />

    \frac{du}{dx} = -\frac{3x^2 - 6x + 4}{(3x^2-4)^2}

    so ...

    \frac{d}{dx} (e^u) = e^u \cdot \frac{du}{dx} = -e^{\frac{x-1}{3x^2-4}} \cdot \frac{3x^2 - 6x + 4}{(3x^2-4)^2}
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  6. #6
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    Thank you, I guess I tried to simplify too much.. I am curious about the plus 4 in the numerator. Shouldn't that be a minus 4?

    Also are you using a separate program to write the math equations and then pasting it into your reply?
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