\(\text{www.the}\beta\text{etafunction.com}\)
Home
Login
Questions: Algebra BusinessCalculus
Please login to create an exam or a quiz.
Find the linearization of \(\displaystyle f(x) = \sqrt{x}\) at \(\displaystyle x = 49\) and use it to approximate \(\displaystyle \sqrt{67}\). Leave your solution as a rational number.
The formula for the linearization of \(\displaystyle f\) at \(\displaystyle x=a\) is: \(\displaystyle L(x)=f'(a)(x-a)+f(a)\). \(\displaystyle f(49) = 7\) and caclulating the derivative gives \(\displaystyle f'(x) = \frac{1}{2 \sqrt{x}}\) and \(\displaystyle f'(49)=\frac{1}{14}\). The linearization is \(\displaystyle L(x)=\frac{1}{14} \left(x - 49\right) + 7 = \frac{x}{14} + \frac{7}{2}\)This gives the approximation \(\displaystyle \sqrt{67} \approx L(67) = \frac{58}{7}\).
\begin{question}Find the linearization of $f(x) = \sqrt{x}$ at $x = 49$ and use it to approximate $\sqrt{67}$. Leave your solution as a rational number. \soln{9cm}{The formula for the linearization of $f$ at $x=a$ is: $L(x)=f'(a)(x-a)+f(a)$. $f(49) = 7$ and caclulating the derivative gives $f'(x) = \frac{1}{2 \sqrt{x}}$ and $f'(49)=\frac{1}{14}$. The linearization is $L(x)=\frac{1}{14} \left(x - 49\right) + 7 = \frac{x}{14} + \frac{7}{2}$This gives the approximation $\sqrt{67} \approx L(67) = \frac{58}{7}$. } \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 linearization of <img class="equation_image" title=" \displaystyle f(x) = \sqrt{x} " src="/equation_images/%20%5Cdisplaystyle%20f%28x%29%20%3D%20%5Csqrt%7Bx%7D%20" alt="LaTeX: \displaystyle f(x) = \sqrt{x} " data-equation-content=" \displaystyle f(x) = \sqrt{x} " /> at <img class="equation_image" title=" \displaystyle x = 49 " src="/equation_images/%20%5Cdisplaystyle%20x%20%3D%2049%20" alt="LaTeX: \displaystyle x = 49 " data-equation-content=" \displaystyle x = 49 " /> and use it to approximate <img class="equation_image" title=" \displaystyle \sqrt{67} " src="/equation_images/%20%5Cdisplaystyle%20%5Csqrt%7B67%7D%20" alt="LaTeX: \displaystyle \sqrt{67} " data-equation-content=" \displaystyle \sqrt{67} " /> . Leave your solution as a rational number. </p> </p>
<p> <p>The formula for the linearization of <img class="equation_image" title=" \displaystyle f " src="/equation_images/%20%5Cdisplaystyle%20f%20" alt="LaTeX: \displaystyle f " data-equation-content=" \displaystyle f " /> at <img class="equation_image" title=" \displaystyle x=a " src="/equation_images/%20%5Cdisplaystyle%20x%3Da%20" alt="LaTeX: \displaystyle x=a " data-equation-content=" \displaystyle x=a " /> is: <img class="equation_image" title=" \displaystyle L(x)=f'(a)(x-a)+f(a) " src="/equation_images/%20%5Cdisplaystyle%20L%28x%29%3Df%27%28a%29%28x-a%29%2Bf%28a%29%20" alt="LaTeX: \displaystyle L(x)=f'(a)(x-a)+f(a) " data-equation-content=" \displaystyle L(x)=f'(a)(x-a)+f(a) " /> . <img class="equation_image" title=" \displaystyle f(49) = 7 " src="/equation_images/%20%5Cdisplaystyle%20f%2849%29%20%3D%207%20" alt="LaTeX: \displaystyle f(49) = 7 " data-equation-content=" \displaystyle f(49) = 7 " /> and caclulating the derivative gives <img class="equation_image" title=" \displaystyle f'(x) = \frac{1}{2 \sqrt{x}} " src="/equation_images/%20%5Cdisplaystyle%20f%27%28x%29%20%3D%20%5Cfrac%7B1%7D%7B2%20%5Csqrt%7Bx%7D%7D%20" alt="LaTeX: \displaystyle f'(x) = \frac{1}{2 \sqrt{x}} " data-equation-content=" \displaystyle f'(x) = \frac{1}{2 \sqrt{x}} " /> and <img class="equation_image" title=" \displaystyle f'(49)=\frac{1}{14} " src="/equation_images/%20%5Cdisplaystyle%20f%27%2849%29%3D%5Cfrac%7B1%7D%7B14%7D%20" alt="LaTeX: \displaystyle f'(49)=\frac{1}{14} " data-equation-content=" \displaystyle f'(49)=\frac{1}{14} " /> . The linearization is <img class="equation_image" title=" \displaystyle L(x)=\frac{1}{14} \left(x - 49\right) + 7 = \frac{x}{14} + \frac{7}{2} " src="/equation_images/%20%5Cdisplaystyle%20L%28x%29%3D%5Cfrac%7B1%7D%7B14%7D%20%5Cleft%28x%20-%2049%5Cright%29%20%2B%207%20%3D%20%5Cfrac%7Bx%7D%7B14%7D%20%2B%20%5Cfrac%7B7%7D%7B2%7D%20" alt="LaTeX: \displaystyle L(x)=\frac{1}{14} \left(x - 49\right) + 7 = \frac{x}{14} + \frac{7}{2} " data-equation-content=" \displaystyle L(x)=\frac{1}{14} \left(x - 49\right) + 7 = \frac{x}{14} + \frac{7}{2} " /> This gives the approximation <img class="equation_image" title=" \displaystyle \sqrt{67} \approx L(67) = \frac{58}{7} " src="/equation_images/%20%5Cdisplaystyle%20%5Csqrt%7B67%7D%20%5Capprox%20L%2867%29%20%3D%20%5Cfrac%7B58%7D%7B7%7D%20" alt="LaTeX: \displaystyle \sqrt{67} \approx L(67) = \frac{58}{7} " data-equation-content=" \displaystyle \sqrt{67} \approx L(67) = \frac{58}{7} " /> . </p> </p>