This week's book / license giveaways are in the JDBC and Relational Databases and Java in General forums. We're giving away four copies each of PostGIS in Action and Java Advanced Topics Training and have the authors on-line! See this thread and this one for details.

The class java.lang.Math has so many numeric functions like exponential, log and trigonometric. sin, cos and tan are some of the trigonometric functions. Note that Math is a static class and you don't have to instantiate to use these functions.