Unit Circle

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In this lesson, we will learn how to define our six trigonometric functions using the unit circle. Since the radius is 1 on the unit circle, we can find the sin θ as the y-coordinate of the intersecting point and cos θ as the x-coordinate of the intersecting point. We can then find tan θ as x/y and the remaining three functions using the reciprocal identities. Additionally, we will learn how to set up the unit circle for trigonometry. This will allow us to solve problems really quickly. Lastly, we will learn about the definition of a circular function. This involves using s, the arc length instead of θ an angle measure in radians.
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