Trig Functions

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Trig Functions

• Sine, Cosine, Tangent

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Labels for Right Triangles
If we know one angle, we know all the angles. So
we measure all things in relation to the angle.
Hypotenuse
Opposite Side
Angle
Opposite to what?
Adjacent Side
The Angle
Adjacent to what?
The Angle
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The Trig Functions
Hypotenuse
Opposite Side
Sine, Cosine, Tangent
Angle
Adjacent Side
SOH
Sine, opposite, hypotenuse
Get these from the triangle.
Get this from your calculator
CAH
TOA
Cosine, adjacent, hypotenuse
Tangent, opposite, adjacent
adj hyp
Cos( Angle)
Get these from the triangle.
Get these from the triangle.
Get this from your calculator
Get this from your calculator
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The Trig Functions
Example problems
opp
Angle
Example 1 Find a if A 15 and b 8.
Angle
opp
adj
adj
Which trig function do we use????
TOA
Tangent, opposite, adjacent
a 8
Tan( 15 )
from calculator
from triangle
0.267 a/8 a 2.14
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Model triangle
The Trig Functions
Example problems
opp
Angle
Example 2 Find b if A 75 and a 18.
Angle
opp
adj
adj
Which trig function do we use????
TOA
Tangent, opposite, adjacent
18 b
Tan( 75 )
from calculator
from triangle
3.73 18/b b 4.82