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
4. Polynomial Functions
Dividing Polynomials
Problem 57
Textbook Question
Use synthetic division to determine whether the given number k is a zero of the polyno-mial function. If it is not, give the value of ƒ(k). ƒ(x) = x^2 - 2x + 2; k = 1-i
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1
Identify the polynomial function \( f(x) = x^2 - 2x + 2 \) and the complex number \( k = 1-i \).
Set up synthetic division using \( k = 1-i \). Write the coefficients of the polynomial: \( 1, -2, 2 \).
Perform synthetic division: Bring down the leading coefficient (1) as the first entry in the bottom row.
Multiply \( 1 \) by \( k = 1-i \) and add the result to the next coefficient (-2).
Continue the process: Multiply the new entry by \( k = 1-i \) and add to the next coefficient (2).
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Synthetic Division
Synthetic division is a simplified method for dividing a polynomial by a linear factor of the form (x - c). It involves using the coefficients of the polynomial and performing a series of multiplications and additions to find the quotient and remainder. This technique is particularly useful for evaluating polynomials at specific values and determining if those values are roots.
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Polynomial Functions
A polynomial function is a mathematical expression involving a sum of powers in one or more variables multiplied by coefficients. The general form is ƒ(x) = a_nx^n + a_(n-1)x^(n-1) + ... + a_1x + a_0, where n is a non-negative integer. Understanding the structure of polynomial functions is essential for analyzing their behavior, including finding zeros and evaluating the function at specific points.
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Complex Numbers
Complex numbers are numbers that have a real part and an imaginary part, expressed in the form a + bi, where 'a' is the real part and 'b' is the coefficient of the imaginary unit 'i' (where i^2 = -1). In this context, evaluating the polynomial at a complex number like k = 1 - i requires understanding how to perform arithmetic operations with complex numbers, which is crucial for determining the value of ƒ(k).
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Dividing Complex Numbers
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