Need help with trig

Question

Need help with trig

anonymous · Answer

Find the exact value of sin-1(-1)
Find the exact value of tan-1 ((√3)/3)
The first negative is supposed to be like the inverse. 
I just need to learn how to do these kinds of problems

anonymous · Answer

@amistre64 Could you help me out?

thesmartone · Answer

So 

$\sf\Large sin(x) = y$

then
$\sf\Large sin^{-1}(y)=x$

Same goes for the tangent.

anonymous · Answer

I understand that concept but I'm not sure what to do now. Divide by sin? or you just have to find what times sine makes sine equals  -1?

dtan5457 · Answer

When it's to the ^-1, I'm pretty sure you find what angle makes sin=-1. Same with your 2nd question.

dtan5457 · Answer

SO instead of radians you have the actual degree

anonymous · Answer

-90?

dtan5457 · Answer

sin=the y coordinate 

-1 would be a quadrantal angle

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dtan5457 · Answer

shouldn't be a negative degree, and it's not 90

thesmartone · Answer

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anonymous · Answer

-90?

dtan5457 · Answer

i said it's not, look at where on the graph y=-1

anonymous · Answer

270?

thesmartone · Answer

@dtan5457 -90 degrees = 270 degrees :P

dtan5457 · Answer

i like 270 better

thesmartone · Answer

Soo the second question :P

dtan5457 · Answer

but yeah, both work @brucewayne23

anonymous · Answer

Thanks guys. I'm sorry for the confusion. lemme do the 2nd one and see what i get. I'll be back in like 5 min

thesmartone · Answer

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anonymous · Answer

ok this one is hard. how do you do it for tangent? i know it has to be 1st or 3rd quadrant but idk what else

dtan5457 · Answer

it's not hard if you know the 30-60-90 triangle

thesmartone · Answer

correct, so I drew a triangle in the 1st quadrant, let's label an angle as 'x'
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