4.3 Right Triangle Trigonometry
The Six Trigonometric Functions
csc θ =
sin θ =
sec θ =
cos θ =
cot θ =
tan θ =
opposite = side opposite the angle that never touches it
adjacent = side that touches the angle that is not the
hypotenuse
hypotenuse = longest side, side opposite 90 angle
Ex. 1
Given 2 sides:
a=3 and b=4
sinθ= cscθ=
cosθ= secθ=
tanθ= cotθ=
a 2 + b 2 = c2
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Ex. 2 Given angle θ = 45 degrees
csc θ =
sin θ =
cos θ =
sec θ =
tan θ =
cot θ =
Ex. 3 Given angle θ = 60 degrees
sin θ =
csc θ =
cos θ =
sec θ =
tan θ =
cot θ =
p. 382 *know these reference angles
Cofunctions:
sin(90-θ)=cosθ
ASSN: p.387,388 1-21 odd
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