Addition and Subtraction Formulas
Videos and lessons to help High School students learn how to prove the addition and
subtraction formulas for sine, cosine, and tangent and use them to solve problems.
Trig Identities Sine Addition and Subtraction
Proof of the Sine angle sum/difference identity.
Trig Identities Cosine Addition and Subtraction
Proof of the Cosine angle sum/difference identity.
Trig Identities Tangent and using the identities
Proof of the Tangent angle sum/difference identity.
Trig Identities
The fundamental trig identities and some strategies for solving beginning general trigonometric identities.
Sum and Difference Identities for Sine
Use the sum and difference sine identity to determine function values.
Sum and Difference Identities for Cosine
Use the sum and difference cosine identity to determine function values.
Sum and Difference Identities for Tangent
Use the sum and difference tangent identity to determine function values.
Cosine addition identity example.
Proof of the Sine angle sum/difference identity.
Trig Identities Cosine Addition and Subtraction
Proof of the Cosine angle sum/difference identity.
Trig Identities Tangent and using the identities
Proof of the Tangent angle sum/difference identity.
Trig Identities
The fundamental trig identities and some strategies for solving beginning general trigonometric identities.
Sum and Difference Identities for Sine
Use the sum and difference sine identity to determine function values.
Sum and Difference Identities for Cosine
Use the sum and difference cosine identity to determine function values.
Sum and Difference Identities for Tangent
Use the sum and difference tangent identity to determine function values.
Cosine addition identity example.
Try out our new and fun Fraction Concoction Game.
Add and subtract fractions to make exciting fraction concoctions following a recipe. There are four levels of difficulty: Easy, medium, hard and insane. Practice the basics of fraction addition and subtraction or challenge yourself with the insane level.
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