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Find the derivative of \(\displaystyle y = \frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}}\)
Taking the natural logarithm of both sides of the equation and expanding the right hand side gives: \begin{equation*}\ln(y) = \ln{\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right)} \end{equation*} Expanding the right hand side using the product and quotient properties of logarithms gives: \begin{equation*}\ln(y) = \frac{7 \ln{\left(6 x + 7 \right)}}{2} + 4 \ln{\left(7 x + 7 \right)}- x - 2 \ln{\left(x \right)} - 5 \ln{\left(2 x - 4 \right)} - 5 \ln{\left(7 x - 5 \right)} \end{equation*} Taking the derivative on both sides of the equation yields: \begin{equation*}\frac{y'}{y} = -1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x} \end{equation*} Solving for \(\displaystyle y'\) and substituting out y using the original equation gives \begin{equation*}y' = \left(-1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x}\right)\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right) \end{equation*}
\begin{question}Find the derivative of $y = \frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}}$
\soln{9cm}{Taking the natural logarithm of both sides of the equation and expanding the right hand side gives:
\begin{equation*}\ln(y) = \ln{\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right)} \end{equation*}
Expanding the right hand side using the product and quotient properties of logarithms gives:
\begin{equation*}\ln(y) = \frac{7 \ln{\left(6 x + 7 \right)}}{2} + 4 \ln{\left(7 x + 7 \right)}- x - 2 \ln{\left(x \right)} - 5 \ln{\left(2 x - 4 \right)} - 5 \ln{\left(7 x - 5 \right)} \end{equation*}
Taking the derivative on both sides of the equation yields:
\begin{equation*}\frac{y'}{y} = -1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x} \end{equation*}
Solving for $y'$ and substituting out y using the original equation gives
\begin{equation*}y' = \left(-1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x}\right)\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right) \end{equation*}
}
\end{question}
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\begin{document}\begin{question}(10pts) The question goes here!
\soln{9cm}{The solution goes here.}
\end{question}\end{document}<p> <p>Find the derivative of <img class="equation_image" title=" \displaystyle y = \frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} " src="/equation_images/%20%5Cdisplaystyle%20y%20%3D%20%5Cfrac%7B%5Cleft%287%20x%20%2B%207%5Cright%29%5E%7B4%7D%20%5Csqrt%7B%5Cleft%286%20x%20%2B%207%5Cright%29%5E%7B7%7D%7D%20e%5E%7B-%20x%7D%7D%7Bx%5E%7B2%7D%20%5Cleft%282%20x%20-%204%5Cright%29%5E%7B5%7D%20%5Cleft%287%20x%20-%205%5Cright%29%5E%7B5%7D%7D%20" alt="LaTeX: \displaystyle y = \frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} " data-equation-content=" \displaystyle y = \frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} " /> </p> </p><p> <p>Taking the natural logarithm of both sides of the equation and expanding the right hand side gives:
<img class="equation_image" title=" \ln(y) = \ln{\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right)} " src="/equation_images/%20%5Cln%28y%29%20%3D%20%5Cln%7B%5Cleft%28%5Cfrac%7B%5Cleft%287%20x%20%2B%207%5Cright%29%5E%7B4%7D%20%5Csqrt%7B%5Cleft%286%20x%20%2B%207%5Cright%29%5E%7B7%7D%7D%20e%5E%7B-%20x%7D%7D%7Bx%5E%7B2%7D%20%5Cleft%282%20x%20-%204%5Cright%29%5E%7B5%7D%20%5Cleft%287%20x%20-%205%5Cright%29%5E%7B5%7D%7D%20%5Cright%29%7D%20%20%20" alt="LaTeX: \ln(y) = \ln{\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right)} " data-equation-content=" \ln(y) = \ln{\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right)} " />
Expanding the right hand side using the product and quotient properties of logarithms gives:
<img class="equation_image" title=" \ln(y) = \frac{7 \ln{\left(6 x + 7 \right)}}{2} + 4 \ln{\left(7 x + 7 \right)}- x - 2 \ln{\left(x \right)} - 5 \ln{\left(2 x - 4 \right)} - 5 \ln{\left(7 x - 5 \right)} " src="/equation_images/%20%5Cln%28y%29%20%3D%20%5Cfrac%7B7%20%5Cln%7B%5Cleft%286%20x%20%2B%207%20%5Cright%29%7D%7D%7B2%7D%20%2B%204%20%5Cln%7B%5Cleft%287%20x%20%2B%207%20%5Cright%29%7D-%20x%20-%202%20%5Cln%7B%5Cleft%28x%20%5Cright%29%7D%20-%205%20%5Cln%7B%5Cleft%282%20x%20-%204%20%5Cright%29%7D%20-%205%20%5Cln%7B%5Cleft%287%20x%20-%205%20%5Cright%29%7D%20%20%20" alt="LaTeX: \ln(y) = \frac{7 \ln{\left(6 x + 7 \right)}}{2} + 4 \ln{\left(7 x + 7 \right)}- x - 2 \ln{\left(x \right)} - 5 \ln{\left(2 x - 4 \right)} - 5 \ln{\left(7 x - 5 \right)} " data-equation-content=" \ln(y) = \frac{7 \ln{\left(6 x + 7 \right)}}{2} + 4 \ln{\left(7 x + 7 \right)}- x - 2 \ln{\left(x \right)} - 5 \ln{\left(2 x - 4 \right)} - 5 \ln{\left(7 x - 5 \right)} " />
Taking the derivative on both sides of the equation yields:
<img class="equation_image" title=" \frac{y'}{y} = -1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x} " src="/equation_images/%20%5Cfrac%7By%27%7D%7By%7D%20%3D%20-1%20%2B%20%5Cfrac%7B28%7D%7B7%20x%20%2B%207%7D%20-%20%5Cfrac%7B35%7D%7B7%20x%20-%205%7D%20%2B%20%5Cfrac%7B21%7D%7B6%20x%20%2B%207%7D%20-%20%5Cfrac%7B10%7D%7B2%20x%20-%204%7D%20-%20%5Cfrac%7B2%7D%7Bx%7D%20%20%20" alt="LaTeX: \frac{y'}{y} = -1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x} " data-equation-content=" \frac{y'}{y} = -1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x} " />
Solving for <img class="equation_image" title=" \displaystyle y' " src="/equation_images/%20%5Cdisplaystyle%20y%27%20" alt="LaTeX: \displaystyle y' " data-equation-content=" \displaystyle y' " /> and substituting out y using the original equation gives
<img class="equation_image" title=" y' = \left(-1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x}\right)\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right) " src="/equation_images/%20y%27%20%3D%20%5Cleft%28-1%20%2B%20%5Cfrac%7B28%7D%7B7%20x%20%2B%207%7D%20-%20%5Cfrac%7B35%7D%7B7%20x%20-%205%7D%20%2B%20%5Cfrac%7B21%7D%7B6%20x%20%2B%207%7D%20-%20%5Cfrac%7B10%7D%7B2%20x%20-%204%7D%20-%20%5Cfrac%7B2%7D%7Bx%7D%5Cright%29%5Cleft%28%5Cfrac%7B%5Cleft%287%20x%20%2B%207%5Cright%29%5E%7B4%7D%20%5Csqrt%7B%5Cleft%286%20x%20%2B%207%5Cright%29%5E%7B7%7D%7D%20e%5E%7B-%20x%7D%7D%7Bx%5E%7B2%7D%20%5Cleft%282%20x%20-%204%5Cright%29%5E%7B5%7D%20%5Cleft%287%20x%20-%205%5Cright%29%5E%7B5%7D%7D%20%5Cright%29%20%20%20" alt="LaTeX: y' = \left(-1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x}\right)\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right) " data-equation-content=" y' = \left(-1 + \frac{28}{7 x + 7} - \frac{35}{7 x - 5} + \frac{21}{6 x + 7} - \frac{10}{2 x - 4} - \frac{2}{x}\right)\left(\frac{\left(7 x + 7\right)^{4} \sqrt{\left(6 x + 7\right)^{7}} e^{- x}}{x^{2} \left(2 x - 4\right)^{5} \left(7 x - 5\right)^{5}} \right) " />
</p> </p>