Graph each polynomial function. Factor first if the polynomial is not in factored form. ƒ(x)=2x3-5x2-x+6
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- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations1h 43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 5m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 22m
- 10. Combinatorics & Probability1h 45m
4. Polynomial Functions
Understanding Polynomial Functions
Problem 45
Textbook Question
Graph each polynomial function. Factor first if the polynomial is not in factored form. ƒ(x)=3x4-7x3-6x2+12x+8
Verified step by step guidance1
Start by writing down the polynomial function: \(f(x) = 3x^4 - 7x^3 - 6x^2 + 12x + 8\).
Attempt to factor the polynomial. Since it is a quartic (degree 4), try factoring by grouping or use the Rational Root Theorem to find possible roots.
Use the Rational Root Theorem to list possible rational roots: factors of the constant term (8) over factors of the leading coefficient (3), which gives possible roots \(\pm1, \pm2, \pm4, \pm8, \pm\frac{1}{3}, \pm\frac{2}{3}, \pm\frac{4}{3}, \pm\frac{8}{3}\).
Test these possible roots by substituting them into \(f(x)\) or by using synthetic division to find which values make the polynomial equal to zero, thus identifying factors.
Once a root is found, factor out the corresponding binomial (e.g., \((x - r)\)) and continue factoring the resulting polynomial until it is fully factored or cannot be factored further; then use the factored form to analyze and graph the function.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Polynomial Factoring
Factoring a polynomial involves rewriting it as a product of simpler polynomials, which helps identify its roots and simplifies graphing. Techniques include factoring out the greatest common factor, grouping, or using special formulas like difference of squares or sum/difference of cubes.
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Introduction to Factoring Polynomials
Finding Roots of a Polynomial
Roots (or zeros) are the values of x where the polynomial equals zero. After factoring, setting each factor equal to zero gives the roots, which correspond to x-intercepts on the graph. Knowing roots helps in sketching the polynomial's graph accurately.
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Imaginary Roots with the Square Root Property
Graphing Polynomial Functions
Graphing involves plotting key points such as roots, y-intercept, and analyzing end behavior based on the leading term. The degree and leading coefficient determine the shape and direction of the graph, while multiplicity of roots affects how the graph touches or crosses the x-axis.
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Graphing Polynomial Functions
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