Finding inverse sine, cosine and tangent without calculator.

• May 2nd 2010, 08:46 PM
goonodeath
Finding inverse sine, cosine and tangent without calculator.
Hi guys...I have a math test tomorrow and one of the sections involves finding inverse sine operations without using a calculator.

For example Sin-1(2)

Now I know how to find regular sine using the unit circle but how do you do inverse without a calculator?

Thanks to anyone who can help.
• May 2nd 2010, 09:19 PM
pickslides
Consider this relationship

$\sin \left(\frac{\pi}{4}\right) = \frac{1}{\sqrt{2}}$

Do you know how this was solved?

Therefore

$\frac{\pi}{4} =\sin^{-1} \left( \frac{1}{\sqrt{2}}\right)$
• May 2nd 2010, 10:03 PM
goonodeath
^Thank you...you just boosted my grade from an f to a passing grade.(Clapping)

On an unrelated note do you play guitar? Pickslides sounds like a guitar thing...you know picks and slides.
• May 2nd 2010, 10:20 PM
pickslides
Quote:

Originally Posted by goonodeath

On an unrelated note do you play guitar?

Yep, loves it.