Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

Published by Pearson
ISBN 10: 0-32193-104-1
ISBN 13: 978-0-32193-104-7

Chapter 3 - Polynomial and Rational Functions - Section 3.2 The Real Zeros of a Polynomial Function - 3.2 Assess Your Understanding - Page 225: 79

Answer

$f(0)=-1$ and $f(1)=10$ This shows that $f(0)$ and $f(1)$ attains opposite variations. So, as per the Intermediate Value Theorem, there must be a real zero in the interval $[0,1]$.

Work Step by Step

We are given that $f(x)=8x^4-2x^2+5x-1$ The Intermediate Value Theorem states that when a function is continuous on an interval $[p,q]$ and takes values $f(p)$ and $f(q)$ at the endpoints, then the function takes all values between $f(p)$ and $f(q)$ at some point of the interval. We will evaluate the function at the endpoints $[0,1]$. $f(0)=8(0)^4-2(0)^2+5(0)-1=0-0+0-1=-1$ $f(1)=8(1)^4-2(1)^2+5(1)-1=8-2+5-1=10$ This shows that $f(0)$ and $f(1)$ attains opposite variations. So, as per the Intermediate Value Theorem, there must be a real zero in the interval $[0,1]$.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.