Problem 1 Finding the Domain of Validity
What is the domain of validity of each trigonometric identity?
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The domain of
Therefore the domain of validity of
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The domain of validity is the same as part (a), because sec
Plan
How can an expression be undefined?
An expression could contain a denominator that could be zero or it could contain an expression that is itself undefined for some values.
✓ Got It?
- What is the domain of validity of the trigonometric identity
You can use known identities to verify other identities. To verify an identity, you can use previously known identities to transform one side of the equation to look like the other side.
Problem 2 Verifying an Identity Using Basic Identities
Verify the identity. What is the domain of validity?
Plan
What identity do you know that you can use?
Look for a way to write the expression on the left in terms of
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The domain of
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The domain of
✓ Got It?
- Verify the identity
Table of Contents
- 5-1 Polynomial Functions
- 5-2 Polynomials, Linear Factors, and Zeros
- 5-3 Solving Polynomial Equations
- 5-4 Dividing Polynomials
- 5-5 Theorems About Roots of Polynomial Equations
- 5-6 The Fundamental Theorem of Algebra
- 5-7 The Binomial Theorem
- 5-8 Polynomial Models in the Real World
- 5-9 Transforming Polynomial Functions