SOLUTION: please help thank you. use a double angle identity to find the exact value 2 cos^2(pi/8)-1

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: please help thank you. use a double angle identity to find the exact value 2 cos^2(pi/8)-1      Log On


   



Question 1085867: please help thank you. use a double angle identity to find the exact value 2 cos^2(pi/8)-1
Answer by ikleyn(52778) About Me  (Show Source):