Lesson 14.5 Right Triangle Trigonometry

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• Lesson 14.5 Right Triangle Trigonometry

• DO NOW Find each value.
• A
• 1. Sin C
• 2. Cos C
• 15 17 3. Tan C
• 4. Sin A
• 5. Cos A
• B 8 C 6. Tan A

1. Define Sin, Cos and Tan of an angle in a
right triangle. 2. How can you describe the
pair of angles A and C?

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• 1) A right triangle has sides 3, 4 and 5. Find
  the sin ratio for the angle opposite the side of
  length 3.

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• 2) A ship leaves port and heads due north at 8
  miles per hour at the same time that another ship
  leaves port and heads due west at 15 miles per
  hour. What is the angle from the second ship to
  the first ship measured from the line of sight to
  port?

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• 3) One angle in a right triangle is 37 and the
  hypotenuse is 10. Find the other angle and two
  sides.

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Cofunction Identities

• The following pairs of trig functions are
• Cofunctions
• sine and COsine
• Secant and COsecant
• Tangent and COtangent

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• 4. Complete the chart below for 5 pairs of
  angles, where a and ß are complementary.

a ß sin a cos ß tan a cot ß sec a csc ß
32 58 .5299




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• Without using a calculator, evaluate
• Arccos .643 Arcsin .643