Today's lesson begins with a review of the homework from page 372-373 1,3,6 (a only), 7-21 odd, 47, 55, 33-39 odd, 51, 58.  The middle of class was spent completing an in-class practice on the Sum and Difference Identities in groups.  The last part of the class was applying the Sum and Difference identities to two problems listed on the overhead.