# If sides A and B of a triangle have lengths of 5 and 2 respectively, and the angle between them is (3pi)/8, then what is the area of the triangle?

The standard formula is $A r e a = \frac{1}{2} b c \setminus \sin \setminus \alpha$, where $b$ and $c$ are the two sides and $\setminus \alpha$ is the angle between them.
So $A r e a = \frac{1}{2} \setminus \times 5 \setminus \times 2 \setminus \times \setminus \sin \left(\frac{3 \setminus \pi}{8}\right) = 4.62$.