Determine the different possibilities for the numbers of positive, negative, and nonreal complex zeros of each function.
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- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
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- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
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4. Polynomial Functions
Zeros of Polynomial Functions
Problem 3
Textbook Question
Determine whether each statement is true or false. If false, explain why. For ƒ(x)=(x+2)4(x-3), the number 2 is a zero of multiplicity 4.
Verified step by step guidance1
Recall that the zeros of a function are the values of \( x \) that make \( f(x) = 0 \).
Given \( f(x) = (x+2)^4 (x-3) \), the zeros come from setting each factor equal to zero: \( x+2=0 \) and \( x-3=0 \).
Solving these, we find the zeros are \( x = -2 \) and \( x = 3 \).
The multiplicity of a zero is the exponent on the factor corresponding to that zero. For \( x = -2 \), the multiplicity is 4 because of the \( (x+2)^4 \) term.
Since the problem states the number 2 is a zero of multiplicity 4, but the zero with multiplicity 4 is actually \( -2 \), the statement is false.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Zeros of a Function
A zero of a function is a value of x for which the function equals zero. To find zeros, set the function equal to zero and solve for x. Each zero corresponds to a root of the equation, indicating where the graph crosses or touches the x-axis.
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Multiplicity of a Zero
Multiplicity refers to how many times a particular zero appears as a factor in the function. For example, if (x - a)^n is a factor, then x = a is a zero of multiplicity n. The multiplicity affects the graph's behavior at that zero, such as whether it crosses or just touches the x-axis.
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Factoring and Identifying Zeros from Polynomial Expressions
To identify zeros and their multiplicities, express the polynomial in factored form. Each factor of the form (x - c)^k indicates a zero at x = c with multiplicity k. Understanding how to read and interpret these factors is essential for analyzing the function's roots.
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Introduction to Factoring Polynomials
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