# Homework Hints 10-2

### Note: Homework Hints are given only for the Level 1 and Level 2 problems.

However, as you go through the book be sure you look at all the examples in the text. If you need hints for the Level 3 problems, check some sources for help on the internet (see the LINKS for that particular section. As a last resort, you can call the author at (707) 829-0606.

On the other hand, the problems designated “Problem Solving” generally require techniques that do not have textbook examples.

There are many sources for homework help on the internet.

Algebra.help
Here is a site where technology meets mathematics. You can search a particular topic or choose lessons, calculators, worksheets for extra practice or other resources.
http://www.algebrahelp.com/

Dr. Math is a registered trademark. This is an excellent site at which you can search to see if your question has been previously asked, or you can send your question directly to Dr. Math to receive an answer.
http://mathforum.org/dr.math/

Quick Math
This site provides online graphing calculators. This is especially useful if you do not have your own  calculator.
http://www.quickmath.com/

The Math Forum @ Drexel
This site provides an internet mathematics library that can help if you need extra help. For additional homework help at this site, click one of the links in the right-hand column.
http://mathforum.org/

Problems 1-4
There are many problems throughout the text labeled IN YOUR OWN WORDS. Just relax; do not be afraid to give your opinion. For the most part, these questions do not have “right” or “wrong” answers. You should spend about five minutes in answering each of these questions.
Problems 5-18
These problems are testing your knowledge of the definition of logarithm, as well as the fundamental property of logarithms.
Problems 19-20
Use the Grant’s tomb properties to answer find these values.  Do not use a calculator or a paper and pencil because these answers should be obvious.  If they are not, then you are not understanding the definition of logarithm.
Problems 21-24
Do not use your calculator, but do these problems mentally by thinking about the definition of logarithm.
For example, in Problem 21a think, “What is the exponent on a base 5 that gives 25?”
In Problem 23a, think “5 is the exponent on a base 10 which gives the value x?
Problems 25-28
Use the properties of logarithms; see Example 3.
Problems 29-32
Use the given pH formula. Use your calculator and substitute into the formula the given value and  simplify.
Problems 33-34
Here are two nice applications of logarithmic equations.  Evaluate these formulas using the given value.
Problems 35-42
The a and b parts of these problems should be compared as you do these problems. Part a is an equation from beginning algebra. As you do this part think about what you are doing to solve for x. Then, when you are doing part b, notice that this part uses the same steps that you used in part a.
For example, in Problem 35, the first step is to add 2 to both sides; note in part b, log 100 is the number 2. The second step is to multiply both sides by 2 to find the value of x in part a and the value of log x in part b. Once you have a value for log x, use the definition of logarithm to solve for x.
Problems 43-54
Use the definition of logarithms; see Example 5.