MathTools is a full-featured math calculator for the Mac. It can tackle both simple operations like addition, subtraction, multiplication, division, powers, and square roots, and more complicated operations like logarithms, sines, and cosines, tangents and hyperbolic sines, cosines, and tangents, among many others.
The first window that you will see when you launch this application is the basic operations window. Here, you can input the numbers that you want to use in your calculations. When you are done, you simply have to click on "Calculate" and the results will be shown. Both negative and positive numbers can be used in the fields, but fractions didn't return accurate results.
You can access the more advanced calculation windows from the menubar menus. They all work the same, you type in the numbers and the results are shown.
There is a nice tool called "Analyzer" which returns relevant information about a number you enter. For example, if you type in the number "5", the application will tell you to what group of numbers it belongs (in this case, N), the previous and next number in N, divisors, and equivalent fraction.
In short, this is a nice tool for math students. It is easy to use and very comprehensive.