Math 181 Miniproject 4: Linear Approximation and Calculus.md --- Math 181 Miniproject 4: Linear Approximation and Calculus === **Overview:** In this miniproject you will put the idea of the *local linearization* of a function to build linear approximations to complex functions and then make *interpolations* and *extrapolations* using them. **Prerequisites:** Sections 1.8 in *Active Calculus*, which focuses on this topic. **Completion of Miniprojects 1 and 2 is recommended before doing this miniproject**. --- :::info 1\. A potato is placed in an oven, and the potato's temperature $F$ (in degrees Fahrenheit) at various points in time is taken and recorded in the following table. The time $t$ is measured in minutes. | $t$ | 0 | 15 | 30 | 45 | 60 | 75 | 90 | |----- |---- |------- |----- |----- |------- |------- |------- | | $F$ | 70 | 180.5 | 251 | 296 | 324.5 | 342.8 | 354.5 | (a) Use a central difference to estimate $F'(75)$. Use this estimate as needed in subsequent questions in this problem. ::: (a) $f'(75)=\frac{f(90)-f(60)}{90-60}=\frac{354.5-324.5}{90-60}=\frac{30}{30}=1\frac{F}{min}$ :::info (b) Find the local linearization $y = L(t)$ to the function $y = F(t)$ at the point where $a = 75$. ::: (b) $L(t)=f(a)+f'(a)(x-a)$ $L(75)=f(75)+f'(75)(x-75)$ $L(75)=342.8+1(x-75)$ :::info (c\) Determine an estimate for $F(72)$ by employing the local linearization. Terminology: This estimate is called an *interpolation* because we are estimating a value that lies within a data set, between two known data points. ::: (c\) $F(72)=L(72)=342.8+1(72-75)= 339.8$ $Fahrenheit$ :::info (d) Do you think your estimate in (c) is too large, too small, or exactly right? Why? ::: (d) I believe the estimate is exactly right since the temperature is lower than the temperature value at 75 minutes. :::info (e) Use your local linearization to estimate $F(100)$. Terminology: This estimate is called an *extrapolation* because we are estimating a value that lies outside the range of values of a data set. ::: (e) $F(100)=L(100)=342.8+1(100-75)=367.8$ $Fahrenheit$ :::info (f) Do you think your estimate in (e) is too large, too small, or exactly right? Why? ::: (f) I think the estimate is exactly right because the temperature is higher than the temperature value at 90 minutes. :::info (g) Plot both $F$ and $L$ and comment on how or when the line $L(t)$ is a good approximation of $F(t)$. ::: (g) The line L(t) is not a good approximation of F(t) because when plotted, they are not directly on top of eachother. ![](https://i.imgur.com/JkYaHVm.png) --- To submit this assignment click on the Publish button ![Publish button icon](https://i.imgur.com/Qk7vi9V.png). Then copy the url of the final document and submit it in Canvas.