# help with inverse trigonometric functions

• November 24th 2010, 01:23 PM
wonderd
help with inverse trigonometric functions
I am stuck on these 2 problems and was wondering if someone could work them out for me?

http://i232.photobucket.com/albums/e...Untitled-1.png
• November 24th 2010, 02:48 PM
skeeter
what have you tried ?
• November 24th 2010, 02:56 PM
Plato
• November 24th 2010, 03:20 PM
wonderd
this is a brilliant tool thank you very much! But i do have one problem. For this problem sin&#40;arccos 2&#47;5 - arctan5&#41; - Wolfram|Alpha I need exact form and it gives it ot me in decimal. What can I do?
• November 24th 2010, 04:30 PM
skeeter
Quote:

Originally Posted by wonderd
this is a brilliant tool thank you very much! But i do have one problem. For this problem sin&#40;arccos 2&#47;5 - arctan5&#41; - Wolfram|Alpha I need exact form and it gives it ot me in decimal. What can I do?

work it out by hand using the difference identity for sine and some right triangle trig.
• November 24th 2010, 04:41 PM
wonderd
would someone be willing to work it out for me?
• November 24th 2010, 06:33 PM
Prove It
What does $\displaystyle \tan{45^{\circ}}$ equal? What is the inverse cosine of that?