Q. Find the following trigonometric values.Express your answers exactly.cos(47π)=sin(47π)=
Understand the unit circle: Understand the unit circle and the values of cosine and sine for special angles.The unit circle allows us to find the values of sine and cosine for multiples of π/4, π/2, π, and so on. The angles (7π/4) and (π/4) are coterminal, meaning they share the same terminal side on the unit circle. Therefore, cos((7π/4)) and sin((7π/4)) will have the same absolute values as cos((π/4)) and sin((π/4)), but possibly different signs depending on the quadrant in which the angle (7π/4) lies.
Determine the quadrant: Determine the quadrant in which the angle (7π/4) lies.The angle (7π/4) is more than 2π but less than 2π+π/4, which means it is in the fourth quadrant of the unit circle. In the fourth quadrant, cosine is positive and sine is negative.
Calculate cos(47π): Calculate the value of cos(47π).Since 47π is coterminal with 4π, and we know that cos(4π)=22, we can say that cos(47π)=22 because cosine is positive in the fourth quadrant.
Calculate sin(47π): Calculate the value of sin(47π). Similarly, since 47π is coterminal with 4π, and we know that sin(4π)=22, we can say that sin(47π)=−22 because sine is negative in the fourth quadrant.
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