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Explain how the special angles are used to find the coordinates points around the Unit Circle and how you find the sine, cosine, and tangent values of the special angles using the Unit Circle.

User Metheny
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Answer:

Explanation:

The Unit Circle is a circle with a radius of 1 unit that is centered at the origin of a coordinate plane. It is often used in trigonometry to understand the relationships between angles, coordinates, and trigonometric functions such as sine, cosine, and tangent.

Special angles in trigonometry are angles that have commonly used values for their trigonometric functions. These special angles are 0 degrees, 30 degrees, 45 degrees, 60 degrees, and 90 degrees, and their corresponding angles in radians (which are the preferred units for angles in the Unit Circle). These angles have well-defined coordinates on the Unit Circle, and their sine, cosine, and tangent values can be easily determined.

To find the coordinates of points on the Unit Circle for special angles, we can use the following steps:

Start with the angle in radians. For example, if we are finding the coordinates for the angle of 30 degrees, we convert it to radians by multiplying by the conversion factor pi/180 (since there are pi radians in 180 degrees): 30 degrees * (pi/180) = pi/6 radians.

Identify the coordinates on the Unit Circle that correspond to the angle in radians. For example, for an angle of pi/6 radians, we know that it is located in the first quadrant of the Unit Circle, and the coordinates of the point where the angle intersects the Unit Circle are (cos(pi/6), sin(pi/6)).

Use the values of cosine and sine for the special angle from trigonometric tables or from memory. For example, the cosine of pi/6 radians is sqrt(3)/2, and the sine of pi/6 radians is 1/2.

Substitute the cosine and sine values into the coordinates of the Unit Circle. For example, for the angle of 30 degrees or pi/6 radians, the coordinates on the Unit Circle are (cos(pi/6), sin(pi/6)) = (sqrt(3)/2, 1/2).

Use the tangent function to find the tangent value of the special angle. The tangent function is defined as the ratio of sine to cosine: tan(theta) = sin(theta) / cos(theta). For example, for the angle of pi/6 radians, the tangent value is (sin(pi/6)) / (cos(pi/6)) = (1/2) / (sqrt(3)/2) = 1/sqrt(3).

In summary, special angles in trigonometry are used to determine the coordinates of points on the Unit Circle, and the sine, cosine, and tangent values of these special angles can be found using trigonometric tables or from memory, and then applied to the Unit Circle to determine the coordinates and trigonometric function values for these angles.

User Thomasd
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