Table of contents
- 0. Review of Algebra4h 16m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 6m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 19m
- 10. Combinatorics & Probability1h 45m
0. Review of Algebra
Polynomials Intro
Problem 16
Textbook Question
In Exercises 15–32, multiply or divide as indicated. (6x+9)/(3x−15) ⋅ (x−5)/(4x+6)
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1
Factor the numerators and denominators where possible. For the first fraction, factor out a 3 from the numerator and factor the denominator as a difference of squares. For the second fraction, factor out a 2 from the denominator.
Simplify the expressions by canceling out common factors in the numerator and denominator across the fractions.
Multiply the simplified numerators together and the simplified denominators together to form a new fraction.
Check if the resulting fraction can be simplified further by factoring and reducing any common factors.
Write the final expression in its simplest form.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Rational Expressions
Rational expressions are fractions where the numerator and/or denominator are polynomials. Understanding how to manipulate these expressions, including simplifying, multiplying, and dividing them, is crucial for solving problems involving them. In this case, the expression (6x+9)/(3x−15) is a rational expression that can be simplified before performing operations.
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Factoring Polynomials
Factoring polynomials involves rewriting a polynomial as a product of its factors. This is essential for simplifying rational expressions, as it allows for cancellation of common factors in the numerator and denominator. For example, both the numerator and denominator in the given expression can be factored to reveal simpler forms that facilitate multiplication and division.
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Multiplication of Rational Expressions
When multiplying rational expressions, the process involves multiplying the numerators together and the denominators together. It is important to simplify the resulting expression by canceling any common factors before finalizing the answer. This method ensures that the multiplication is performed correctly and efficiently, leading to a simplified result.
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