Unit+8+Journal+Responses

__** Unit 8: Exponential Functions **__

=== Journal Assignments: All due dates are listed on your teacher's site (when the journal entry should be finished).===

**__ 8.1: __**
In your online journal:
 * Identify each variable in an exponential growth model and say what it represents.
 * Only looking at an equation, how would you determine if the function represents a growth model or a decay model?
 * Also, copy the equation into your notebook for class and have each variable labeled to be ready for class.

Given the scenario below, use the equation to find p(2) and explain in complete sentences what you have just determined in the context of the situation.


 * The population of Jacksonville was 3,810 in 2007, and is growing at an annual rate of 3.5%. The population of Jacksonville can be modeled by the function P(t) = 3810(1.035)^t.**

**__ 8.2: __**
Look at the graph below. Both exponential growth models represent two different bank accounts.


 * The blue exponential growth model represents a bank account where a person deposited $1000 with a $50 bonus for signing up. The account has a 4.99% interest rate and the interest is compounded annually.**


 * The red exponential growth model represents a bank account where a person deposited $1000. The account has a 5.99% interest rate and the interest is compounded monthly.**
 * Compare and contrast the two bank accounts in your online journal by answering the following questions:**
 * Write a function that represents the red exponential growth model.
 * What is the y-intercept of each function? Explain in the context of the situation.
 * Which account is better? Is this always true? Be specific, using dates and account values from the graph to support your argument.
 * Which account would you choose when opening to save up for your college in a few years and why?
 * Would you choose that same account to start your child's college fund (if you had a child) and why?

**__ 8.3: __**
In your journal, make a list of your first 3 quarter grades and your midterm grade. You can find this information on your report card or in X2 (NOT FROM YOUR TEACHER!!). We are going to assume that you get a 60% on your final exam. List this grade in your journal as well.

Your assignment is to calculate the grade you will need to earn 4th quarter so that you are able to reach the "goal grade" that you set for yourself in journal entry 6.4. Go back to this journal entry and list this as your "final grade" in this journal entry.

Here is how calculating grades is done... Add up all 4 quarter grades and then divide by 4 (this is finding the average) Multiply that value by 0.8 (because these count as 80% of your total grade) Add 10% of your midterm grade (multiply 0.10 times your midterm grade) Add 10% of your final grade This is your Final Grade in the class.

Your task is to first write an equation that shows all of these steps in one problem, using x as the missing 4th quarter grade. (This is not an exponential equation - hint: there are NO exponents involved.) Solve this equation for x to determine what the needed 4th quarter grade is. Add this grade to the list in your journal as your 4th quarter grade. Is this grade attainable for you? Are you on track with your goals?

**__ 8.4: __**
Attached is a document with 8 math problems already solved. In complete sentences, identify where the error is made and how it can be corrected. There are 8 problems, so there should be 8 errors and 8 correct methods to match in your online journal.

In your classroom binder, you are to redo all 8 problems correctly. Be sure not to make the same error that was already done. (Hint: you should have different answers than the ones in the document.)