Question

How do you find the sine, cosine, and tangent values on the unit circle not in the first quadrant? Provide an example, and how you would find the sine, cosine, and tangent of the value you chose

Answer 1

A point (-0.8, 0.6) will be a point on the unit circle in the second quadrant. Since it is a unit circle, its radius is 1, and we have
  sin(α) = y = 0.6
  cos(α) = x = -0.8
  tan(α) = y/x = 0.6/-0.8 = -0.75

The angle is α = arccos(-0.8) ≈ 143.13°

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For the unit circle, the trig values are always the coordinates or their ratio as shown above, regardless of quadrant.