Skip to main content
Ch. 3 - Polynomial and Rational Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 4, Problem 45

For each polynomial function, use the remainder theorem to find ƒ(k). ƒ(x) = 6x4 + x3 - 8x2 + 5x+6; k=1/2

Verified step by step guidance
1
Recall the Remainder Theorem: For a polynomial ƒ(x), the remainder when divided by (x - k) is equal to ƒ(k). So, to find ƒ(k), we simply evaluate the polynomial at x = k.
Write down the polynomial function and substitute x with k = \(\frac{1}{2}\): \[ƒ\left(\frac{1}{2}\right) = 6\left(\frac{1}{2}\right)^4 + \left(\frac{1}{2}\right)^3 - 8\left(\frac{1}{2}\right)^2 + 5\left(\frac{1}{2}\right) + 6\]
Calculate each term separately: - Compute \(6\left(\frac{1}{2}\right)^4\) - Compute \(\left(\frac{1}{2}\right)^3\) - Compute \(-8\left(\frac{1}{2}\right)^2\) - Compute \(5\left(\frac{1}{2}\right)\) - The constant term is 6
Add all the computed values together to find the value of ƒ\(\left\)(\(\frac{1}{2}\)\(\right\)). This sum represents the remainder when ƒ(x) is divided by \(x - \frac{1}{2}\).
Thus, the value of ƒ(k) is the remainder according to the Remainder Theorem, completing the problem.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
2m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Polynomial Functions

A polynomial function is an expression consisting of variables and coefficients combined using addition, subtraction, and multiplication, with non-negative integer exponents. Understanding the structure of polynomials helps in evaluating them at specific values and applying theorems related to their behavior.
Recommended video:
06:04
Introduction to Polynomial Functions

Remainder Theorem

The Remainder Theorem states that when a polynomial ƒ(x) is divided by (x - k), the remainder is equal to ƒ(k). This allows us to find the value of the polynomial at k by simply evaluating ƒ(k), without performing full polynomial division.
Recommended video:
05:10
Higher Powers of i

Evaluating Polynomials at a Given Value

Evaluating a polynomial at a specific value involves substituting the value for the variable and simplifying the expression. This process is essential for applying the Remainder Theorem and finding the remainder or function value efficiently.
Recommended video:
Guided course
05:13
Introduction to Polynomials