polynomial functions and graphs unit test

1 answer

Sure! Here are some sample questions that could be included in a unit test on polynomial functions and their graphs. Each question covers key concepts associated with polynomials, their characteristics, and their representations:

Multiple Choice Questions

  1. The degree of a polynomial is defined as:

    • A) The highest exponent of the variable in the polynomial
    • B) The total number of terms in the polynomial
    • C) The highest coefficient of the polynomial
    • D) The sum of the exponents of all terms

    Answer: A) The highest exponent of the variable in the polynomial

  2. Which of the following polynomials is a cubic polynomial?

    • A) \(2x^2 + 3x + 5\)
    • B) \(x^3 - 4x^2 + x - 1\)
    • C) \(5 - 2x\)
    • D) \(x + 1\)

    Answer: B) \(x^3 - 4x^2 + x - 1\)

  3. What is the end behavior of the polynomial \(f(x) = -2x^4 + 3x^3 - x + 1\)?

    • A) Both ends go up
    • B) Both ends go down
    • C) Left goes down, right goes up
    • D) Left goes up, right goes down

    Answer: B) Both ends go down (since the leading coefficient is negative and the degree is even)

Short Answer Questions

  1. State the leading term of the following polynomial:
    \(f(x) = 4x^3 - 2x^2 + 7x - 5\)

    Answer: \(4x^3\)

  2. Find the zeros of the polynomial \(f(x) = x^2 - 5x + 6\).

    Answer: The zeros are \(x = 2\) and \(x = 3\).

Graphing Questions

  1. Graph the polynomial function \(f(x) = (x - 2)(x + 1)\). Identify the x-intercepts and the y-intercept.

    Answer:

    • x-intercepts: \(x = 2\) and \(x = -1\)
    • y-intercept: \(f(0) = (0 - 2)(0 + 1) = -2\)
  2. Describe the symmetry of the polynomial function \(g(x) = x^4 - 3x^2 + 2\).

    Answer: The function is an even polynomial, and thus it has y-axis symmetry.

Problem Solving

  1. Given the polynomial \(h(x) = 2x^3 - 6x^2 + 4x\), factor the polynomial completely.

    Answer: \(h(x) = 2x(x^2 - 3x + 2) = 2x(x - 1)(x - 2)\)

  2. Determine whether the polynomial \(p(x) = x^3 - 4x\) has any local maxima or minima. Find their locations.

    Answer:

    • First, find the critical points by setting \(p'(x) = 0\).
    • \(p'(x) = 3x^2 - 4\)
    • \(0 = 3x^2 - 4\)
    • Thus, \(x^2 = \frac{4}{3}\), leading to \(x = \pm \frac{2}{\sqrt{3}}\).
    • Further investigation using the second derivative test or first derivative test would reveal the nature of these critical points.

Extended Response

  1. Explain how the Fundamental Theorem of Algebra applies to polynomial functions and provide an example.

Answer: The Fundamental Theorem of Algebra states that every non-constant polynomial equation with complex coefficients has as many roots as its degree, counting multiplicities. For example, a polynomial of degree 3, such as \(f(x) = x^3 + 2x^2 + x + 2\), must have exactly 3 roots in the complex number system, which may include real and/or complex roots.


Feel free to use these questions or modify them to fit your specific curriculum or focus areas!