1. which of the following angles is not coterminal with the other three
591°
231 °
51°
-129°
2. Find the cosine 315 °. Round your answers to the nearest hundreth if necessary
0
0.71
1
-0.78
3. Find the radian measure of an angle of -280°
9/-14π
-14π/9
9π/-14
-14/9π
4. Find the radian measure of an angle of 110°
11/18 π
11π/18
18/11π
18π/11
2. -0.71
3. -14π/9
4. 11π/18
1. which of the following angles is not coterminal with the other three
591°
231 °
51°
-129°
51°
1. To determine which angle is not coterminal with the other three, we need to compare their degrees.
591° can be rewritten as 591° - 360° = 231°, so it is coterminal with 231°.
231° is coterminal with itself.
51° can be rewritten as 51° + 360° = 411°, so it is coterminal with 411°.
-129° can be rewritten as -129° + 360° = 231°, so it is coterminal with 231°.
Therefore, the angle that is not coterminal with the other three is 591°.
2. To find the cosine of 315°, we can use the unit circle or a calculator. The cosine of an angle is the x-coordinate on the unit circle.
The cosine of 315° is -0.71 rounded to the nearest hundredth.
3. To find the radian measure of an angle of -280°, we need to convert it from degrees to radians.
1 radian is equal to 180°/π.
So, -280° in radians is (-280°)(π/180°) = -14π/9.
Therefore, the radian measure of an angle of -280° is -14π/9.
4. To find the radian measure of an angle of 110°, we need to convert it from degrees to radians.
1 radian is equal to 180°/π.
So, 110° in radians is (110°)(π/180°) = 11π/18.
Therefore, the radian measure of an angle of 110° is 11π/18.