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# Trigonometry SOH CAH TOA when to do inverse (-1)

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1. when do i know when to do inverse for trig?
2. when you have an angle and the length of one side
3. When you're trying to find the angle rather than the length

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4. normal SOH CAH TOA is when you have an angle and a side, and you want to find out another side.
The inverse is used when you have two sides and want to find out an angle

eg:
sin(x) = 1/2
you can't type in 0.5/sin into your calculator, so to get x by itself, you have to do the inverse of sin:
x= sin-1(1/2)
x = 30
5. (Original post by surina16)
normal SOH CAH TOA is when you have an angle and a side, and you want to find out another side.
The inverse is used when you have two sides and want to find out an angle
thanks
6. (Original post by Divinchi)
thanks
7. You use inverse trig functions when you have for example, sinx= .. Cosx=... Tanx=...
You're trying to find the angle, x, such that sinx= some value.
For example if sinx=0.5 then .
You may see written as .

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Updated: May 31, 2016
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