Determine if the given function is a polynomial function. If so, write in standard form, then state the degree and leading coefficient.
Table of contents
- 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
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Find the zeros of the given polynomial function and give the multiplicity of each. State whether the graph crosses or touches the x-axis at each zero. f(x)=2x4−12x3+18x2
A
Touch at x=0, Cross at x=−3
B
Touch at x=0, Touch at x=3
C
Touch at x=1, Cross at x=−3
D
Touch at x=−1, Cross at x=0

1
First, factor out the greatest common factor from the polynomial f(x) = 2x^4 - 12x^3 + 18x^2. Notice that each term has a factor of 2x^2.
After factoring out 2x^2, the polynomial becomes f(x) = 2x^2(x^2 - 6x + 9).
Next, factor the quadratic expression x^2 - 6x + 9. Recognize that this is a perfect square trinomial, which can be factored as (x - 3)^2.
Now, the polynomial is expressed as f(x) = 2x^2(x - 3)^2. Identify the zeros by setting each factor equal to zero: 2x^2 = 0 and (x - 3)^2 = 0.
Solve for x in each equation: 2x^2 = 0 gives x = 0 with multiplicity 2, and (x - 3)^2 = 0 gives x = 3 with multiplicity 2. Since both zeros have even multiplicities, the graph touches the x-axis at x = 0 and x = 3.
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Understanding Polynomial Functions practice set
