Core Connections Integrated III, 2015
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Core Connections Integrated III, 2015 View details
1. Section 9.1
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Exercise 45 Page 447

The x- and y-coordinate are given by cos θ and sin θ, respectively.

P(0.643,0.766)
Q(- 0.342,0.939)

Practice makes perfect

Notice that in a unit circle the x-coordinate is given by cos θ, and the y-coordinate by sin θ.

If we evaluate the trigonometric expressions for x and y, we can determine the coordinates in decimal form. P(cos 50^(∘),sin 50^(∘)) & ⇔ P(0.643,0.766) Q(cos 110^(∘),sin 110^(∘)) & ⇔ Q(- 0.342,0.939)