Here’s the link to an easier on-line graphing calculator:
http://my.hrw.com/math06_07/nsmedia/tools/Graph_Calculator/graphCalc.html
Sum and Difference identities for:
cos (u – v) = cos u cos v + sin u sin v
cos (u+v) = cos u cos v – sin u sin v
sin (u – v) = sin u cos v – cos u sin v
sin (u+v) = sin u cos v + cos u sin v
tan ( u + v) = (tan u + tan v) ÷ (1 - tan u•tan v)
tan ( u - v) = (tan u - tan v) ÷ (1 + tan u•tan v)
Double- Angle Formulas:
sin 2u = 2 sin u cos u
cos 2u = cos²u – sin²u OR 1 – 2sin²u OR 2cos²u – 1
