Drawing the reference triangles for trig and inverse trig functions?

I understand which quadrants house each positive function, but am unsure how you determine the quadrant that these functions go in.
ex-
1.) sin^-1(1)

2.) tan^-1(-1)

3.)sec^-1(1/2)

4.) csc^-1(-sqrt(2))

1 Answer
Mar 14, 2018

3 rules:

  • (1) Know that cos, sec functions are restricted to quad 1 and 2
  • (2) Know that tan, cot, sin, csc are restricted to quad 1 and 4
  • (3) And when you go to quadrant 4 with tan, cot, sin, csc, use negative angles

1) arcsin(1)= pi/2
2) arctan(-1)= -pi/4
3) arcsec(1/2)= DNE
4) arc csc (-sqrt2)= -pi/4