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)= F(90)-F(60)/90-60 = (354.5-324.5)/30 =1 :::info (b) Find the local linearization $y = L(t)$ to the function $y = F(t)$ at the point where $a = 75$. ::: (b) F'(75)[t-75] =L(t)-F(75) L(t-75) =L(t)-48 L(t)=t+267.8 :::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) = 72+267.8 F(72) = 339.8 estimation based on L(t) :::info (d) Do you think your estimate in (c) is too large, too small, or exactly right? Why? ::: (d) By looking at the data we see that F' is decreasing which also means it is concaving down, therefore the tangent lines to F are above the function of F. Which means that F(72) is an **overestimate** :::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) Backwards quotient difference: F'(90)= (F'(75)-F(90))/75-90 =342.8-354.5/-15 =F'(90)=0.78 y=L(t) L(t)= F'(90)(t-90)+F(90) =0/78(t-90)+354.5 L(t)= 0.78t + 284.3 F(100)=L(100) 0.78x100+284.3 F(100)=362.3 :::info (f) Do you think your estimate in (e) is too large, too small, or exactly right? Why? ::: (f) I think that my estimation is way too large compared to what it should be as F(100) should be around t= 1-15 :::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![](https://i.imgur.com/ofmoNQ9.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.