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Ch. 3 - Polynomial and Rational Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063당신이 사용하는 게 아니라요?교과서 변경
4장, 문제 32b

Show that each polynomial function has a real zero as described in parts (a) and (b). In Exercises 31 and 32, also work part (c). ƒ(x)=4x3-37x2+50x+60 between 7 and 8

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First, understand that to show a polynomial function has a real zero between two values, we can use the Intermediate Value Theorem. This theorem states that if a continuous function changes sign over an interval, then it must have at least one root in that interval.
Evaluate the function \( f(x) = 4x^3 - 37x^2 + 50x + 60 \) at the endpoints of the interval, which are \( x = 7 \) and \( x = 8 \). Calculate \( f(7) \) and \( f(8) \) separately.
Check the signs of \( f(7) \) and \( f(8) \). If one is positive and the other is negative, then by the Intermediate Value Theorem, there is at least one real zero between 7 and 8.
To further confirm, you can use methods such as the bisection method or graphing to approximate the root more precisely within the interval.
Summarize that since the function is a polynomial (which is continuous everywhere) and the function values at 7 and 8 have opposite signs, the function must have a real zero between 7 and 8.

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주요 개념

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