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Math Help - Derivatives

  1. #1
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    Post Derivatives

    Find derivative dy/dx if

    a) y=tan^-1(1/2x)

    b) y=4^(-x+3)

    thanks!
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  2. #2
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    Quote Originally Posted by live_laugh_luv27 View Post
    Find derivative dy/dx if

    a) y=tan^-1(1/2x)

    b) y=4^(-x+3)

    thanks!
    For the first function, just use the chain rule. Do you know how to show that \frac{d}{dx}tan^{-1}(x)=\frac{1}{1+x^2} ?

    The derivative of y=tan^{-1}(\frac{1}{2x}) is just \frac{1}{1+(\frac{1}{2x})^2}(\frac{du}{dx}) where u=\frac{1}{2x}

    See if you can finish it.
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  3. #3
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    y=4^{-x+3}

    You can use the formula \frac{d}{dx}(a^x)=a^xln(a) and the chain rule.
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