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 41
Textbook Question
For each polynomial function, use the remainder theorem to find ƒ(k). ƒ(x) = x^2 + 4; k = 2i
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1
Identify the polynomial function \( f(x) = x^2 + 4 \) and the value \( k = 2i \).
Recall the Remainder Theorem, which states that the remainder of the division of a polynomial \( f(x) \) by \( x - k \) is \( f(k) \).
Substitute \( k = 2i \) into the polynomial function \( f(x) \) to find \( f(2i) \).
Calculate \( f(2i) = (2i)^2 + 4 \).
Simplify the expression \( (2i)^2 + 4 \) by calculating \( (2i)^2 = 4i^2 \) and using the fact that \( i^2 = -1 \).
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
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 of a polynomial in one variable is f(x) = a_n*x^n + a_(n-1)*x^(n-1) + ... + a_1*x + a_0, where 'n' is a non-negative integer and 'a_n' are constants. Understanding polynomial functions is essential for analyzing their behavior and properties.
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Introduction to Polynomial Functions
Remainder Theorem
The Remainder Theorem states that when a polynomial f(x) is divided by a linear divisor of the form (x - k), the remainder of this division is equal to f(k). This theorem allows us to evaluate the polynomial at specific points without performing long division, making it a powerful tool for finding function values efficiently.
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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, 'b' is the imaginary part, and 'i' is the imaginary unit defined as the square root of -1. In this question, k = 2i is a purely imaginary number, and understanding how to work with complex numbers is crucial for evaluating polynomial functions at such points.
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