\(\text{www.the}\beta\text{etafunction.com}\)
Home
Login
Questions: Algebra BusinessCalculus

Please login to create an exam or a quiz.

Calculus
Derivatives
New Random

Find the derivative of \(\displaystyle y = (- 7 x^{2} + 5 x + 7)(9 x^{2} - 5 x + 9)(\sin{\left(x \right)})\).


Identifying \(\displaystyle f=- 7 x^{2} + 5 x + 7\) and \(\displaystyle g=\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)}\) and using the product rule with \(\displaystyle f=- 7 x^{2} + 5 x + 7 \implies f'=5 - 14 x\). This leaves g as \(\displaystyle g = \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)}\) which also requires the product rule. Pushing down in the new product rule \(\displaystyle f=9 x^{2} - 5 x + 9 \implies f'=18 x - 5\) and \(\displaystyle g=\sin{\left(x \right)} \implies g'=\cos{\left(x \right)}\). Popping up a level gives \(\displaystyle g'=(\sin{\left(x \right)})(18 x - 5)+(9 x^{2} - 5 x + 9)(\cos{\left(x \right)})\)Popping up again (Back to the original problem) gives \(\displaystyle f'=(- 7 x^{2} + 5 x + 7)(\left(18 x - 5\right) \sin{\left(x \right)} + \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)})+(\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)})(5 - 14 x)=\left(5 - 14 x\right) \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} + \left(18 x - 5\right) \left(- 7 x^{2} + 5 x + 7\right) \sin{\left(x \right)} + \left(- 7 x^{2} + 5 x + 7\right) \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)}\)

Download \(\LaTeX\)

\begin{question}Find the derivative of $y = (- 7 x^{2} + 5 x + 7)(9 x^{2} - 5 x + 9)(\sin{\left(x \right)})$.
    \soln{9cm}{Identifying $f=- 7 x^{2} + 5 x + 7$ and $g=\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)}$ and using the product rule with $f=- 7 x^{2} + 5 x + 7 \implies f'=5 - 14 x$. This leaves g as $g = \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)}$ which also requires the product rule. Pushing down in the new product rule $f=9 x^{2} - 5 x + 9 \implies f'=18 x - 5$ and $g=\sin{\left(x \right)} \implies g'=\cos{\left(x \right)}$. Popping up a level gives $g'=(\sin{\left(x \right)})(18 x - 5)+(9 x^{2} - 5 x + 9)(\cos{\left(x \right)})$Popping up again (Back to the original problem) gives $f'=(- 7 x^{2} + 5 x + 7)(\left(18 x - 5\right) \sin{\left(x \right)} + \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)})+(\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)})(5 - 14 x)=\left(5 - 14 x\right) \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} + \left(18 x - 5\right) \left(- 7 x^{2} + 5 x + 7\right) \sin{\left(x \right)} + \left(- 7 x^{2} + 5 x + 7\right) \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)}$}

\end{question}

Download Question and Solution Environment\(\LaTeX\)
\documentclass{article}
\usepackage{tikz}
\usepackage{amsmath}
\usepackage[margin=2cm]{geometry}
\usepackage{tcolorbox}

\newcounter{ExamNumber}
\newcounter{questioncount}
\stepcounter{questioncount}

\newenvironment{question}{{\noindent\bfseries Question \arabic{questioncount}.}}{\stepcounter{questioncount}}
\renewcommand{\labelenumi}{{\bfseries (\alph{enumi})}}

\newif\ifShowSolution
\newcommand{\soln}[2]{%
\ifShowSolution%
\noindent\begin{tcolorbox}[colframe=blue,title=Solution]#2\end{tcolorbox}\else%
\vspace{#1}%
\fi%
}%
\newcommand{\hideifShowSolution}[1]{%
\ifShowSolution%
%
\else%
#1%
\fi%
}%
\everymath{\displaystyle}
\ShowSolutiontrue

\begin{document}\begin{question}(10pts) The question goes here!
    \soln{9cm}{The solution goes here.}

\end{question}\end{document}
HTML for Canvas
<p> <p>Find the derivative of  <img class="equation_image" title=" \displaystyle y = (- 7 x^{2} + 5 x + 7)(9 x^{2} - 5 x + 9)(\sin{\left(x \right)}) " src="/equation_images/%20%5Cdisplaystyle%20y%20%3D%20%28-%207%20x%5E%7B2%7D%20%2B%205%20x%20%2B%207%29%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%29%28%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%29%20" alt="LaTeX:  \displaystyle y = (- 7 x^{2} + 5 x + 7)(9 x^{2} - 5 x + 9)(\sin{\left(x \right)}) " data-equation-content=" \displaystyle y = (- 7 x^{2} + 5 x + 7)(9 x^{2} - 5 x + 9)(\sin{\left(x \right)}) " /> .</p> </p>
HTML for Canvas
<p> <p>Identifying  <img class="equation_image" title=" \displaystyle f=- 7 x^{2} + 5 x + 7 " src="/equation_images/%20%5Cdisplaystyle%20f%3D-%207%20x%5E%7B2%7D%20%2B%205%20x%20%2B%207%20" alt="LaTeX:  \displaystyle f=- 7 x^{2} + 5 x + 7 " data-equation-content=" \displaystyle f=- 7 x^{2} + 5 x + 7 " />  and  <img class="equation_image" title=" \displaystyle g=\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} " src="/equation_images/%20%5Cdisplaystyle%20g%3D%5Cleft%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%5Cright%29%20%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%20" alt="LaTeX:  \displaystyle g=\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} " data-equation-content=" \displaystyle g=\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} " />  and using the product rule with  <img class="equation_image" title=" \displaystyle f=- 7 x^{2} + 5 x + 7 \implies f'=5 - 14 x " src="/equation_images/%20%5Cdisplaystyle%20f%3D-%207%20x%5E%7B2%7D%20%2B%205%20x%20%2B%207%20%5Cimplies%20f%27%3D5%20-%2014%20x%20" alt="LaTeX:  \displaystyle f=- 7 x^{2} + 5 x + 7 \implies f'=5 - 14 x " data-equation-content=" \displaystyle f=- 7 x^{2} + 5 x + 7 \implies f'=5 - 14 x " /> . This leaves g as  <img class="equation_image" title=" \displaystyle g = \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} " src="/equation_images/%20%5Cdisplaystyle%20g%20%3D%20%5Cleft%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%5Cright%29%20%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%20" alt="LaTeX:  \displaystyle g = \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} " data-equation-content=" \displaystyle g = \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} " />  which also requires the product rule. Pushing down in the new product rule  <img class="equation_image" title=" \displaystyle f=9 x^{2} - 5 x + 9 \implies f'=18 x - 5 " src="/equation_images/%20%5Cdisplaystyle%20f%3D9%20x%5E%7B2%7D%20-%205%20x%20%2B%209%20%5Cimplies%20f%27%3D18%20x%20-%205%20" alt="LaTeX:  \displaystyle f=9 x^{2} - 5 x + 9 \implies f'=18 x - 5 " data-equation-content=" \displaystyle f=9 x^{2} - 5 x + 9 \implies f'=18 x - 5 " />  and  <img class="equation_image" title=" \displaystyle g=\sin{\left(x \right)} \implies g'=\cos{\left(x \right)} " src="/equation_images/%20%5Cdisplaystyle%20g%3D%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%20%5Cimplies%20g%27%3D%5Ccos%7B%5Cleft%28x%20%5Cright%29%7D%20" alt="LaTeX:  \displaystyle g=\sin{\left(x \right)} \implies g'=\cos{\left(x \right)} " data-equation-content=" \displaystyle g=\sin{\left(x \right)} \implies g'=\cos{\left(x \right)} " /> . Popping up a level gives  <img class="equation_image" title=" \displaystyle g'=(\sin{\left(x \right)})(18 x - 5)+(9 x^{2} - 5 x + 9)(\cos{\left(x \right)}) " src="/equation_images/%20%5Cdisplaystyle%20g%27%3D%28%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%29%2818%20x%20-%205%29%2B%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%29%28%5Ccos%7B%5Cleft%28x%20%5Cright%29%7D%29%20" alt="LaTeX:  \displaystyle g'=(\sin{\left(x \right)})(18 x - 5)+(9 x^{2} - 5 x + 9)(\cos{\left(x \right)}) " data-equation-content=" \displaystyle g'=(\sin{\left(x \right)})(18 x - 5)+(9 x^{2} - 5 x + 9)(\cos{\left(x \right)}) " /> Popping up again (Back to the original problem) gives  <img class="equation_image" title=" \displaystyle f'=(- 7 x^{2} + 5 x + 7)(\left(18 x - 5\right) \sin{\left(x \right)} + \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)})+(\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)})(5 - 14 x)=\left(5 - 14 x\right) \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} + \left(18 x - 5\right) \left(- 7 x^{2} + 5 x + 7\right) \sin{\left(x \right)} + \left(- 7 x^{2} + 5 x + 7\right) \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)} " src="/equation_images/%20%5Cdisplaystyle%20f%27%3D%28-%207%20x%5E%7B2%7D%20%2B%205%20x%20%2B%207%29%28%5Cleft%2818%20x%20-%205%5Cright%29%20%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%20%2B%20%5Cleft%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%5Cright%29%20%5Ccos%7B%5Cleft%28x%20%5Cright%29%7D%29%2B%28%5Cleft%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%5Cright%29%20%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%29%285%20-%2014%20x%29%3D%5Cleft%285%20-%2014%20x%5Cright%29%20%5Cleft%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%5Cright%29%20%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%20%2B%20%5Cleft%2818%20x%20-%205%5Cright%29%20%5Cleft%28-%207%20x%5E%7B2%7D%20%2B%205%20x%20%2B%207%5Cright%29%20%5Csin%7B%5Cleft%28x%20%5Cright%29%7D%20%2B%20%5Cleft%28-%207%20x%5E%7B2%7D%20%2B%205%20x%20%2B%207%5Cright%29%20%5Cleft%289%20x%5E%7B2%7D%20-%205%20x%20%2B%209%5Cright%29%20%5Ccos%7B%5Cleft%28x%20%5Cright%29%7D%20" alt="LaTeX:  \displaystyle f'=(- 7 x^{2} + 5 x + 7)(\left(18 x - 5\right) \sin{\left(x \right)} + \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)})+(\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)})(5 - 14 x)=\left(5 - 14 x\right) \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} + \left(18 x - 5\right) \left(- 7 x^{2} + 5 x + 7\right) \sin{\left(x \right)} + \left(- 7 x^{2} + 5 x + 7\right) \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)} " data-equation-content=" \displaystyle f'=(- 7 x^{2} + 5 x + 7)(\left(18 x - 5\right) \sin{\left(x \right)} + \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)})+(\left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)})(5 - 14 x)=\left(5 - 14 x\right) \left(9 x^{2} - 5 x + 9\right) \sin{\left(x \right)} + \left(18 x - 5\right) \left(- 7 x^{2} + 5 x + 7\right) \sin{\left(x \right)} + \left(- 7 x^{2} + 5 x + 7\right) \left(9 x^{2} - 5 x + 9\right) \cos{\left(x \right)} " /> </p> </p>