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Standards/Math/South Carolina/PC.FT.9

PC.FT.9

PC.FT Trigonometry
PC.FT.1
PC.FT.2
PC.FT.2a
PC.FT.2b
PC.FT.3
PC.FT.4
PC.FT.5
PC.FT.6
PC.FT.7
PC.FT.8
PC.FT.9

Justify the sum and difference formulas for sine, cosine, and tangent and use them to solve problems.

Khan Academy Resources
Trig identity referenceUsing the trig angle addition identitiesFind trig values using angle addition identitiesTrig angle addition identitiesProof of the tangent angle sum and difference identitiesUsing trig angle addition identities: manipulating expressionsProof of the sine angle addition identityProof of the cosine angle addition identityUsing the tangent angle addition identityFinding trig values using angle addition identitiesUsing trig angle addition identities: finding side lengthsUsing the cosine angle addition identity
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