5­4.1.notebook
February 18, 2014
5.4 Sum and Difference Formulas
Learning Target
We will use the sum and
difference formulas to find
exact trig values for angles
that are not an angle from a
special triangle, such as
We will also use them to verify trig
identities and solve trig equations.
Mar 5­7:51 AM
Sum and Difference Identities
sin(u + v) = sin u cos v + cos u sin v
sin(u - v) = sin u cos v - cos u sin v
cos(u + v) = cos u cos v - sin u sin v
cos( u - v) = cos u cos v + sin u sin v
tan ( u + v) =
tan ( u - v) =
Mar 5­7:59 AM
Find the exact value of cos 75
cos 75 = cos(45 + 30)
= cos 45 cos 30 - sin 45 sin 30
Mar 5­8:04 AM
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5­4.1.notebook
February 18, 2014
Find the exact value of sin
Mar 5­8:07 AM
where
Find the exact value of sin(u + v) given
and
where
Mar 5­8:09 AM
Write cos(arctan 1 + arccos x) as an algebraic expression.
Mar 5­8:15 AM
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February 18, 2014
Simplify
Feb 18­8:13 AM
Simplify the expression
Mar 5­9:17 AM
Find all solutions of
Feb 18­8:16 AM
3
5­4.1.notebook
February 18, 2014
Find all solutions of
Mar 5­9:19 AM
Closure
Find an exact value for cos(-195)
Feb 5­8:40 AM
Assignment
#7
Mar 5­9:28 AM
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5­4.1.notebook
February 18, 2014
Feb 5­8:40 AM
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