Polynomial Degree and Zeros – Practice Questions

This page presents practice questions on the degree of a polynomial and the zeros (roots) of a polynomial with their multiplicities. Complete solutions are provided at the bottom of the page. For additional practice, see our polynomial problem collection.


Question 1

What is the degree of the polynomial \(P\) defined by

\[ P(x) = 2x - 2? \]

Question 2

What is the degree of the polynomial \(P\) defined by

\[ P(x) = 2(x - 2)(x^2 + 5)? \]

Question 3

What is the degree of the polynomial \(P\) defined by

\[ P(x) = -5(x - 2)(x^3 + 5) + x^5? \]

Question 4

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = (x + 2)(x - 1) \]

Question 5

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = (x - 2)^2(x + 4) \]

Question 6

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = (x + 5)^3(x - 6)(-x + 6) \]

Question 7

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = (x + 1)(x + 2) + (x + 1)(x + 2)^2 \]

Question 8

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = (x - 4)(x^2 + 4)^2 \]

Question 9

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = (-x + 3)(x^2 + 2x + 5)^2 \]

Question 10

Give the zeros of the polynomial \(P\) and list their multiplicities:

\[ P(x) = -x(-x - 2)^2(x + 2) \]

Answers

1) Degree \(= 1\)

2) Degree \(= 3\)

3) Degree \(= 5\)

4) Zeros: \[ x = -2 \text{ (multiplicity 1)}, \quad x = 1 \text{ (multiplicity 1)} \]

5) Zeros: \[ x = 2 \text{ (multiplicity 2)}, \quad x = -4 \text{ (multiplicity 1)} \]

6) Zeros: \[ x = -5 \text{ (multiplicity 3)}, \quad x = 6 \text{ (multiplicity 2)} \]

7) Zeros: \[ x = -1,\; x = -2,\; x = -3 \quad \text{(each with multiplicity 1)} \]

8) Zeros: \[ x = 4 \text{ (multiplicity 1)}, \quad x = 2i \text{ (multiplicity 2)}, \quad x = -2i \text{ (multiplicity 2)} \]

9) Zeros: \[ x = 3 \text{ (multiplicity 1)}, \quad x = -1 + 2i \text{ (multiplicity 2)}, \quad x = -1 - 2i \text{ (multiplicity 2)} \]

10) Zeros: \[ x = 0 \text{ (multiplicity 1)}, \quad x = -2 \text{ (multiplicity 3)} \]


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