If A = 45 degrees and B = arcsin(3/5), find the exact value of csc (A - B).

Results 1 to 6 of 6

- May 5th 2009, 09:21 PM #1

- Joined
- Jul 2008
- From
- NYC
- Posts
- 1,489

- May 5th 2009, 09:33 PM #2

- May 6th 2009, 05:20 AM #3

- Joined
- Jul 2008
- From
- NYC
- Posts
- 1,489

- May 6th 2009, 02:42 PM #4

- May 7th 2009, 06:11 AM #5

- Joined
- Jul 2008
- From
- NYC
- Posts
- 1,489

- May 7th 2009, 06:15 AM #6
Note that $\displaystyle B = \arcsin \left( \frac{3}{5}\right) \Rightarrow \sin B = \frac{3}{5}$.

And $\displaystyle \sin B = \frac{3}{5} \Rightarrow \cos B = \frac{4}{5}$ (the postive value is taken because the range of the arcsin function is angles in the 4th and 1st quadrants and cos is postive in these two quadrants).