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) We would first set this function up as: $F'(75)=f(75)-f(45)/(75-45)$ After this we would follow the steps to break it down and solve each part separately. Next, we would substitute the values and set up the equation as: $F'(45)=[342.8-296]/(75-45)$ After subtracting the correct numbers, this then becomes: $F'(75)=52.8/30$ This gives us the final answer of $F'(75)=1$ :::info (b) Find the local linearization $y = L(t)$ to the function $y = F(t)$ at the point where $a = 75$. ::: (b) We need to use the equation form $y-f(a)=f'(a)(t-a)$ We would substitute the values and get $y-342.8=1(t-75)$ and now we need to rearrange the equation to be $y=342.8+(t-75)$ which brings us to our final answer: $y=t+267.8$. :::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\) The estimate for $F(72)$ would be set up as $y=72+267.8$ which added up to $339.8$. :::info (d) Do you think your estimate in (c) is too large, too small, or exactly right? Why? ::: (d) The estimate in C is too large because from the table above, you can tell from the table above that $F(t)$ is decreasing which means $F'(t)$ should be negative and concaves down. :::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)The equation of local linearization: $f(t)=t+267.8$ and then is shown as $F(100)=100+267.8=367.8°F$ :::info (f) Do you think your estimate in (e) is too large, too small, or exactly right? Why? ::: (f) The estimate in E because $t=75$ the line of linearization touches the curve. :::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) It's at/near $t=75$ and with this being said, $L(t)$ is an overestimate. --- 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.