Please login to create an exam or a quiz.
Find the difference quotient of \(\displaystyle f(x)=- 7 x^{3} + 7 x^{2} - 7 x + 1\) .
The difference quotient is \(\displaystyle \frac{f(x+h)-f(x)}{h}\). Evaluating \(\displaystyle f(x+h)=- 7 h - 7 x - 7 \left(h + x\right)^{3} + 7 \left(h + x\right)^{2} + 1\) and expanding gives \(\displaystyle f(x+h)=- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1\) Evaluating the difference quotient gives \(\displaystyle \frac{(- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1)-(- 7 x^{3} + 7 x^{2} - 7 x + 1)}{h}\) Simplifying gives \(\displaystyle \frac{- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h}{h}=- 7 h^{2} - 21 h x + 7 h - 21 x^{2} + 14 x - 7\)
\begin{question}Find the difference quotient of $f(x)=- 7 x^{3} + 7 x^{2} - 7 x + 1$ . \soln{9cm}{The difference quotient is $\frac{f(x+h)-f(x)}{h}$. Evaluating $f(x+h)=- 7 h - 7 x - 7 \left(h + x\right)^{3} + 7 \left(h + x\right)^{2} + 1$ and expanding gives $f(x+h)=- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1$ Evaluating the difference quotient gives $\frac{(- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1)-(- 7 x^{3} + 7 x^{2} - 7 x + 1)}{h}$ Simplifying gives $\frac{- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h}{h}=- 7 h^{2} - 21 h x + 7 h - 21 x^{2} + 14 x - 7$ } \end{question}
\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}
<p> <p>Find the difference quotient of <img class="equation_image" title=" \displaystyle f(x)=- 7 x^{3} + 7 x^{2} - 7 x + 1 " src="/equation_images/%20%5Cdisplaystyle%20f%28x%29%3D-%207%20x%5E%7B3%7D%20%2B%207%20x%5E%7B2%7D%20-%207%20x%20%2B%201%20" alt="LaTeX: \displaystyle f(x)=- 7 x^{3} + 7 x^{2} - 7 x + 1 " data-equation-content=" \displaystyle f(x)=- 7 x^{3} + 7 x^{2} - 7 x + 1 " /> . </p> </p>
<p> <p>The difference quotient is <img class="equation_image" title=" \displaystyle \frac{f(x+h)-f(x)}{h} " src="/equation_images/%20%5Cdisplaystyle%20%5Cfrac%7Bf%28x%2Bh%29-f%28x%29%7D%7Bh%7D%20" alt="LaTeX: \displaystyle \frac{f(x+h)-f(x)}{h} " data-equation-content=" \displaystyle \frac{f(x+h)-f(x)}{h} " /> . Evaluating <img class="equation_image" title=" \displaystyle f(x+h)=- 7 h - 7 x - 7 \left(h + x\right)^{3} + 7 \left(h + x\right)^{2} + 1 " src="/equation_images/%20%5Cdisplaystyle%20f%28x%2Bh%29%3D-%207%20h%20-%207%20x%20-%207%20%5Cleft%28h%20%2B%20x%5Cright%29%5E%7B3%7D%20%2B%207%20%5Cleft%28h%20%2B%20x%5Cright%29%5E%7B2%7D%20%2B%201%20" alt="LaTeX: \displaystyle f(x+h)=- 7 h - 7 x - 7 \left(h + x\right)^{3} + 7 \left(h + x\right)^{2} + 1 " data-equation-content=" \displaystyle f(x+h)=- 7 h - 7 x - 7 \left(h + x\right)^{3} + 7 \left(h + x\right)^{2} + 1 " /> and expanding gives <img class="equation_image" title=" \displaystyle f(x+h)=- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1 " src="/equation_images/%20%5Cdisplaystyle%20f%28x%2Bh%29%3D-%207%20h%5E%7B3%7D%20-%2021%20h%5E%7B2%7D%20x%20%2B%207%20h%5E%7B2%7D%20-%2021%20h%20x%5E%7B2%7D%20%2B%2014%20h%20x%20-%207%20h%20-%207%20x%5E%7B3%7D%20%2B%207%20x%5E%7B2%7D%20-%207%20x%20%2B%201%20" alt="LaTeX: \displaystyle f(x+h)=- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1 " data-equation-content=" \displaystyle f(x+h)=- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1 " /> Evaluating the difference quotient gives <img class="equation_image" title=" \displaystyle \frac{(- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1)-(- 7 x^{3} + 7 x^{2} - 7 x + 1)}{h} " src="/equation_images/%20%5Cdisplaystyle%20%5Cfrac%7B%28-%207%20h%5E%7B3%7D%20-%2021%20h%5E%7B2%7D%20x%20%2B%207%20h%5E%7B2%7D%20-%2021%20h%20x%5E%7B2%7D%20%2B%2014%20h%20x%20-%207%20h%20-%207%20x%5E%7B3%7D%20%2B%207%20x%5E%7B2%7D%20-%207%20x%20%2B%201%29-%28-%207%20x%5E%7B3%7D%20%2B%207%20x%5E%7B2%7D%20-%207%20x%20%2B%201%29%7D%7Bh%7D%20" alt="LaTeX: \displaystyle \frac{(- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1)-(- 7 x^{3} + 7 x^{2} - 7 x + 1)}{h} " data-equation-content=" \displaystyle \frac{(- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h - 7 x^{3} + 7 x^{2} - 7 x + 1)-(- 7 x^{3} + 7 x^{2} - 7 x + 1)}{h} " /> Simplifying gives <img class="equation_image" title=" \displaystyle \frac{- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h}{h}=- 7 h^{2} - 21 h x + 7 h - 21 x^{2} + 14 x - 7 " src="/equation_images/%20%5Cdisplaystyle%20%5Cfrac%7B-%207%20h%5E%7B3%7D%20-%2021%20h%5E%7B2%7D%20x%20%2B%207%20h%5E%7B2%7D%20-%2021%20h%20x%5E%7B2%7D%20%2B%2014%20h%20x%20-%207%20h%7D%7Bh%7D%3D-%207%20h%5E%7B2%7D%20-%2021%20h%20x%20%2B%207%20h%20-%2021%20x%5E%7B2%7D%20%2B%2014%20x%20-%207%20" alt="LaTeX: \displaystyle \frac{- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h}{h}=- 7 h^{2} - 21 h x + 7 h - 21 x^{2} + 14 x - 7 " data-equation-content=" \displaystyle \frac{- 7 h^{3} - 21 h^{2} x + 7 h^{2} - 21 h x^{2} + 14 h x - 7 h}{h}=- 7 h^{2} - 21 h x + 7 h - 21 x^{2} + 14 x - 7 " /> </p> </p>