SOLUTION: I have 2 very similar questions which i dont know what to do with! 1) sin(Sin^-1(3/5))+sin(Sin^-1(-3/5) 2) cos(Artan(4/3))-Arcos(5/13)) Thanks for the help.

Algebra ->  Trigonometry-basics -> SOLUTION: I have 2 very similar questions which i dont know what to do with! 1) sin(Sin^-1(3/5))+sin(Sin^-1(-3/5) 2) cos(Artan(4/3))-Arcos(5/13)) Thanks for the help.      Log On


   



Question 288980: I have 2 very similar questions which i dont know what to do with!
1) sin(Sin^-1(3/5))+sin(Sin^-1(-3/5)
2) cos(Artan(4/3))-Arcos(5/13))
Thanks for the help.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1) sin(Sin^-1(3/5))+sin(Sin^-1(-3/5)
---
= (3/5) + (-3/5)
= 0
-------------------
2) cos(Artan(4/3))-Arcos(5/13))
---
= cos(arctan(4/3))cos(arccos(5/13)) + sin(arctan(4/3))sin(arccos(5/13))
---------
= (3/5)(5/13) + (4/5)(12/13)
---
= (3/13) + (48/65)
---
= (15 + 48)/65
= 63/65
==============================
Cheers,
Stan H.