Trig Skillz

The only trig id variations beyond the pythagorean id's in the homework problems assigned have been double angle formulas. Am I correct in reviewing that? Of course, you must know how to manipulate amplitude, period and shift, but I think that's part of the fundamentals and couldn't be covered as a form of review here. Double angles were covered briefly in my trig course, and they're the only ones I've seen in the problems. Here's my trig sheet that hangs by my table.