Trigonometry
posted by George on .
Thank you STEVE!!!!!
Suppose that Cos (theta) = 1/square root 2
if 0<equal to theta , pi/2 then
sin(theta) =
tan (theta) =
If 3pi/2 less than equal to theta , 2pi then
sin(theta) =
tan (theta) =
I know the trig functions but I feel like I am missing something here. cos (theta) = adj/hyp sin(theta) = opp/hyp...im getting confused with the numbers I am getting..can you help me solve these?

always draw diagrams in the correct quadrants for this kind of stuff.
You know that if cosθ = 1/√2, θ = 45°, and the triangle has sides 1,1,√2
So, in QI, x and y are both positive, and
sinθ = y/r = 1/√2
tanθ = y/x = 1/1 = 1
In QIV, x>0 and y<0, so
sin = y/r = 1/√2
tan = y/x = 1