SOLUTION: Use an Addition or Subtraction Formula to write the expression as a trigonometric function of one number. sin(4π/7) cos(5π/21) − cos(4π/7) sin(5π/21)

Algebra ->  Trigonometry-basics -> SOLUTION: Use an Addition or Subtraction Formula to write the expression as a trigonometric function of one number. sin(4π/7) cos(5π/21) − cos(4π/7) sin(5π/21)       Log On


   

Question 1162185: Use an Addition or Subtraction Formula to write the expression as a trigonometric function of one number.
sin(4π/7) cos(5π/21) − cos(4π/7) sin(5π/21)


Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


sin%28A%29cos%28B%29-cos%28A%29sin%28B%29+=+sin%28A-B%29

Plug in the numbers:



You can finish....