MATH 115 Exam 3 : Study guide - Metric Philatelist

MATH 115
Exam 3 : Study guide
Question 1
Be able to answer a question like this:
In the following equation, what is the value of x?
log 243 x
3
For this question you may show as much or as little work as you want, but in the end
you will need to write down the exact integer value.
Questions 2, 3, and 4
These will be questions like Exercises 13, 14, and 15 on the Chapter 4 Test (p. 392 of
the textbook).
You will need to use the properties of logarithms to expand an expression as a sum,
difference, and/or multiple of logarithms.
You should understand that the final answer cannot contain any exponents or radical
signs.
Make sure that you look at the solutions on p. A73.
Questions 5 and 6
These will be questions like Exercises 16, 17, and 18 on the Chapter 4 Test (p. 392 of
the textbook).
You will need to use the properties of logarithms to condense an expression into a
single quantity.
Again, make sure that you look at the solutions on p. A73.
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Question 7
These will be questions like Exercises 19, 20, 21, and 22 on the Chapter 4 Test (p.
392 of the textbook).
You will need to solve an exponential or logarithmic expression for x. You will
come up with a numerical answer, rounded to a certain number of decimals.
Again, make sure that you look at the solutions on p. A73.
Question 8
This will be a question like Example 10 on p. 332. I will provide you the formula
and tell you the half-life of the substance. Then I will ask you how much of the substance
remains after so many years.
You will come up with a numerical answer, rounded to a certain number of decimals.
Questions 9 and 10
This will be a question exactly like that based upon the study guide sheet posted on
my website. I sent everybody an e-mail about this sheet, and I went over the example in
class on Wednesday (2 November). You may click here to get to the page on my website
containing that sheet.
Question 11 (possible)
There may only be the ten questions just outlined. However, I may ask an 11th
question, and if I do it would be a question like Example 3 on p. 348. This is like Question
4 on Online HW Sections 4.3 and 4.4.
If I do ask an 11th question, I would have you do a question with a fairly small
number. For example, as I did in class on Wednesday (2 November), I would do
something like the following:
Write ln 80 in terms of
ln 4 and
ln 5 . So the answer would be the following:
2 2
ln 80 ln 4 4 5 ln 4 5 ln 4 ln 5 2ln 4 ln 5
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