SOLUTION: Find the exact value of cos (α - ß) if cos α = 1/3 and cos ß = - 1/4 if the terminal side of α lies in IV and the terminal side of ß lies in II. (you must show your solutio

Algebra ->  Trigonometry-basics -> SOLUTION: Find the exact value of cos (α - ß) if cos α = 1/3 and cos ß = - 1/4 if the terminal side of α lies in IV and the terminal side of ß lies in II. (you must show your solutio      Log On


   

Question 1159568: Find the exact value of cos (α - ß) if cos α = 1/3 and cos ß = - 1/4 if the terminal side of α lies in IV and the terminal side of ß lies in II. (you must show your solution)
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
















But hence



Similarly, and I leave the details as an exercise for the student:



Therefore:



The rest is just arithmetic.


John

My calculator said it, I believe it, that settles it