4'24'3 Trigonometric Functions

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4.2/4.3 Trigonometric Functions

• Relative to an angle measure (?) there are three
  side lengths of a right triangle - opposite,
  adjacent, and
• hypotenuse. These three sides can be used to
  create six ratios, which define the six
  trigonometric
• functions - sine, cosine, tangent, cosecant,
  secant, and cotangent.
• sin ? opp csc ? hyp
• hyp opp
• cos ? adj sec ? hyp
• hyp adj
• tan ? opp cot ? adj
• adj opp
• Knowing the value of one trigonometric function
  provides two side lengths of a right triangle. By
  drawing
• the triangle and using the pythagorean theorem,
  the third side length can be determined. Once all
  side

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• If the right triangle is placed in the context of
  the rectangular coordinate system
• sin ? y/r
• cos ? x/r
• tan ? y/x
• Within the parameters of the unit circle (radius
  1), the trig functions simplify to the
  following values
• sin ? y/1 y
• cos ? x/1 x
• tan ? y/x sin ? / cos ?