Game Development Reference
In-Depth Information
chapter 12
Trigonometry
In this chapter, you explore the basic notions of trigonometry. You begin by
reviewing the Pythagorean theorem. Exploring the standard triangle in this way
puts you in a position to begin a preliminary inquiry into the notion of how you
can arrive at a ratio between the lengths of the sides of a triangle from which you
can know the sine of an angle. A further step involves exploring ways to measure
angles. You can measure angles in degrees or radians. A radian can be viewed as
an arc of a circle equal in length to the radius of the circle. Radians allow you
to begin to explore trigonometric ratios and extend the sine ratio. These ratios
consist of those involving the cosine, tangent, cotangent, secant, and cosecant.
Toward familiarizing you with such notions, this chapter addresses the following
topics, among others:
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How the slope of a linear graph relates to the side of a triangle
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Recognizing the standard form of a right triangle
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Transferring knowledge of a right triangle to a coordinate plane
Interpreting a coordinate plane as a circle
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Explaining an angle using a unit circle
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Using a unit circle to explore the trigonometric ratios
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