cos
x/r
Domain: [-1, 1]
Range: [0, pi]
tan
y/x
Domain:[-infinity, infinity]
Range: [-pi/2, pi/2]
Domain: (-infinity, -1], [1, infinity)
Range: [0, pi]
sec
r/x
Domain: (-infinity, -1], [1, infinity)
Range: [-pi/2, pi/2]
csc
r/y
sin
y/r
Domain: [-1, 1]
Range: [-pi/2, pi/2]
Domain:[-infinity, infinity]
Range: [0, pi]
cot
x/y