is your corresponding acute angle for (something). Sine is positive in the first and second quadrants. Also, don't subtract too early.
Answer
t = -0.644 + 2πn
t = 0.644 + 2πn
Example 2
Solve (tan t)2 + 3(tan t) – 4 = 0 on the interval [0, 2π].
Hint
You are looking for 4 angles, one from each quadrant. Two of them are standard angles on the unit circle.
Answer
Example 3
Solve sec (t – 3) = -4.
Hint
The easy to find angle is 1.823 radians. It's in the second quadrant, though, so we need its corresponding acute angle to find the other set of angles.
.
is your corresponding acute angle for (something). Sine is positive in the first and second quadrants. Also, don't subtract 
too early.
