• #### Trigonometric Identities - Concept

##### Math›Trigonometry›Trigonometric Functions
How to use the unit circle to derive the tangent identity and the Pythagorean identity.
• #### Trigonometric Identities - Concept

##### Math›Precalculus›Trigonometric Functions
How to use the unit circle to derive the tangent identity and the Pythagorean identity.
• #### Using Trigonometric Identities - Problem 3

##### Math›Precalculus›Trigonometric Functions
How to prove an identity using a Pythagorean identity and algebra.
• #### Using Trigonometric Identities - Problem 3

##### Math›Trigonometry›Trigonometric Functions
How to prove an identity using a Pythagorean identity and algebra.
• #### Using Trigonometric Identities - Problem 1

##### Math›Trigonometry›Trigonometric Functions
How to prove an identity using a Pythagorean identity and algebra.
• #### Trigonometric Identities - Problem 1

##### Math›Precalculus›Trigonometric Functions
How to use the Pythagorean identity to find cosine and tangent when sine is known.
• #### Using Trigonometric Identities - Problem 1

##### Math›Precalculus›Trigonometric Functions
How to prove an identity using a Pythagorean identity and algebra.
• #### Trigonometric Identities - Problem 1

##### Math›Trigonometry›Trigonometric Functions
How to use the Pythagorean identity to find cosine and tangent when sine is known.
• #### Using Trigonometric Identities - Problem 2

##### Math›Trigonometry›Trigonometric Functions
How to simplify a trigonometric expression using a Pythagorean identity and algebra.
• #### The Identity Matrix - Concept

##### Math›Precalculus›Systems of Linear Equations and Matrices
How to determine the identity matrix of order n.
• #### Using Trigonometric Identities - Problem 2

##### Math›Precalculus›Trigonometric Functions
How to simplify a trigonometric expression using a Pythagorean identity and algebra.
• #### Using Trigonometric Identities - Concept

##### Math›Precalculus›Trigonometric Functions
How to simplify a trigonometric expression by converting to sines and cosines and using algebra.
• #### Using Trigonometric Identities - Concept

##### Math›Trigonometry›Trigonometric Functions
How to simplify a trigonometric expression by converting to sines and cosines and using algebra.
• #### Trigonometric Identities - Problem 2

##### Math›Trigonometry›Trigonometric Functions
How to use the unit circle to show that cosine is an even function, and sine and tangent are odd functions.
• #### Trigonometric Identities - Problem 2

##### Math›Precalculus›Trigonometric Functions
How to use the unit circle to show that cosine is an even function, and sine and tangent are odd functions.
• #### Using the Sine and Cosine Addition Formulas to Prove Identities - Concept

How to use the sine and cosine addition formulas to prove the cofunction identities.
• #### Using the Sine and Cosine Addition Formulas to Prove Identities - Concept

How to use the sine and cosine addition formulas to prove the cofunction identities.