Summary of Chapter 6.1 – 6.3
Terminology:
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Basics:
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Ray – a half line
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Angle – joining of two rays
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Vertex – common endpoint of rays forming an angle
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Coterminal Rays – same endpoint
Special Angles:
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Straight angle -- 180
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Right angle – 90 
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Complementary angles – sum to 90 
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Supplementary angles – sum to 180 
Decimals vs. Degrees/Minutes/Seconds
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60 min in a degree
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60 sec in a minute
Measure of an angle is from initial to terminal side (ray)
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0 is along the x axis
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Positive angles are counterclockwise
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Negative angles are clockwise
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360  is a full revolution
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Quadrant definitions
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Side lengths of:
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45-45-90 triangle
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30-60-90 triangle
Triangle types
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Right triangle – one side is 90
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Acute – all three angles < 90 
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Obtuse – one angle > 90 
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Equilateral – all sides equal
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Isosceles – two sides equal
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Scalene – no sides equal
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Largest side is opposite largest angle, etc.
Similar Triangles
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Equal angles
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Proportional sides
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Definitions of 6 trig functions SOHCAHTOA
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Signs of trig functions in four quadrants: ASTC
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30-60-90 and 45-45-90 trig values
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Using Pythagorean Theorem to find trig values
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Reciprocal Identities