Geom8.3and8.4Part2Angles.notebook
April 08, 2014
Geometry
Ch.8 Notes Page 39
P39 8­3 The Tangent Ratio
8­4 Sine and Cosine Ratios (Part 2)
Feb 21­7:13 AM
Trigonometry
Sine, Cosine, and Tangent
Sin, Cos, and Tan on Graphing Calculator
(Calculators must be in Degree Mode)
Used to find Sides or Angles in a Right Triangle
c = hypotenuse
a
b
Feb 21­11:43 AM
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Geom8.3and8.4Part2Angles.notebook
April 08, 2014
Trigonometry
Relationships of the Sides and angles
a
y
c
x
b
a is opposite of x
b is adjacent to x
b is opposite of y
a is adjacent to y
c is never considered opposite or adjacent
c is always called the Hypotenuse
Feb 21­11:47 AM
Finding Angles
Angles use Inverses
Lengths use Regular calculations.
Find angle y and angle x
3
y
5
x
4
Feb 21­11:48 AM
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Geom8.3and8.4Part2Angles.notebook
April 08, 2014
Inverse Trig Ratios
Get x by itself
by using the Inverse of Sin/Cos/Tan
sin­1 sin x = a
x
b
sin­1 Opposite/Hypot a/c
cos­1 cos x = cos­1 Adjacent/Hypot b/c
tan­1 tan x = tan­1 Opposite/Adjacent a/b
SOHCAHTOA
Feb 21­11:47 AM
Feb 21­7:46 AM
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Geom8.3and8.4Part2Angles.notebook
April 08, 2014
Feb 21­7:50 AM
Feb 21­7:48 AM
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Geom8.3and8.4Part2Angles.notebook
April 08, 2014
Feb 21­7:53 AM
Practice
yo
yo
x
x
10
10
y = 62, what is x?
x = 15, what is y?
Apr 15­10:17 AM
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Geom8.3and8.4Part2Angles.notebook
April 08, 2014
HW #45
8­3 and 8­4 Part2 WS
Please put your name and class period at the top of
the homework. Also include the homework number.
Terms:
Tangent
Sine
Cosine
Identity
Feb 21­7:12 AM
Feb 21­7:46 AM
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