How do I figure out what quadrant a sin,cos, or tan belongs in?

Question

How would I figure out the quadrant it belongs in, for example
sin 1/3
tan 3/4
cos -15
etc etc....


Thanks
Narumi

Answer 1

I understand that you are asking for the angle whose (sin) equals 1/3 ,because sin(1/3) is a number =0.3272
In this case as 0<1/3<1 the corresponding angle can belong to the first or second cuadrant
The angle whose tangent is 3/4 as 3/4>0 lies in the first or third cuadrant.

cos @=-15 can´t be