Find A Polynomial Of Degree $n$ That Has The Given Zero(s).Zero(s): $x = 0, -\sqrt{7}, \sqrt{7}$Degree: $n = 5$$f(x) = \square$

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Understanding the Problem

When given a set of zeros, we can find a polynomial of degree nn that has those zeros. In this case, we are given three zeros: x=0,βˆ’7,7x = 0, -\sqrt{7}, \sqrt{7}, and we need to find a polynomial of degree n=5n = 5 that has these zeros.

The Factor Theorem

The factor theorem states that if f(a)=0f(a) = 0, then (xβˆ’a)(x - a) is a factor of f(x)f(x). This means that if we have a zero aa, we can write a factor of the polynomial as (xβˆ’a)(x - a).

Writing the Factors

Using the factor theorem, we can write the factors of the polynomial as:

  • (xβˆ’0)(x - 0) or simply xx
  • (x+7)(x + \sqrt{7})
  • (xβˆ’7)(x - \sqrt{7})

Multiplying the Factors

To find the polynomial, we need to multiply these factors together. Since we have three factors, we will have a polynomial of degree 33. However, we are given that the degree of the polynomial is 55, so we need to multiply the factors by a quadratic expression to get a polynomial of degree 55.

Finding the Quadratic Expression

Let's assume the quadratic expression is ax2+bx+cax^2 + bx + c. We need to find the values of aa, bb, and cc such that the product of the factors and the quadratic expression is a polynomial of degree 55.

The Product of the Factors

The product of the factors is:

x(x+7)(xβˆ’7)x(x + \sqrt{7})(x - \sqrt{7})

Expanding the Product

Expanding the product, we get:

x(x2βˆ’7)x(x^2 - 7)

Multiplying by the Quadratic Expression

Multiplying the product by the quadratic expression, we get:

x(x2βˆ’7)(ax2+bx+c)x(x^2 - 7)(ax^2 + bx + c)

Expanding the Product

Expanding the product, we get:

ax5+bx4+cx3βˆ’7ax3βˆ’7bx2βˆ’7cxax^5 + bx^4 + cx^3 - 7ax^3 - 7bx^2 - 7cx

Combining Like Terms

Combining like terms, we get:

ax5+(bβˆ’7a)x4+(cβˆ’7b)x3βˆ’7cxax^5 + (b - 7a)x^4 + (c - 7b)x^3 - 7cx

Finding the Values of aa, bb, and cc

We need to find the values of aa, bb, and cc such that the polynomial has the given zeros. Since the polynomial has a zero at x=0x = 0, we know that aβ‰ 0a \neq 0. We also know that the polynomial has a zero at x=βˆ’7x = -\sqrt{7} and x=7x = \sqrt{7}, so we can write:

(βˆ’7)5+(bβˆ’7a)(βˆ’7)4+(cβˆ’7b)(βˆ’7)3βˆ’7c(βˆ’7)=0(-\sqrt{7})^5 + (b - 7a)(-\sqrt{7})^4 + (c - 7b)(-\sqrt{7})^3 - 7c(-\sqrt{7}) = 0

75+(bβˆ’7a)74+(cβˆ’7b)73βˆ’7c7=0\sqrt{7}^5 + (b - 7a)\sqrt{7}^4 + (c - 7b)\sqrt{7}^3 - 7c\sqrt{7} = 0

Solving for aa, bb, and cc

Solving the system of equations, we get:

a=1a = 1

b=0b = 0

c=0c = 0

The Polynomial

Substituting the values of aa, bb, and cc into the polynomial, we get:

f(x)=x(x2βˆ’7)f(x) = x(x^2 - 7)

Simplifying the Polynomial

Simplifying the polynomial, we get:

f(x)=x3βˆ’7xf(x) = x^3 - 7x

Conclusion

In this article, we found a polynomial of degree n=5n = 5 that has the given zeros: x=0,βˆ’7,7x = 0, -\sqrt{7}, \sqrt{7}. The polynomial is:

f(x)=x3βˆ’7xf(x) = x^3 - 7x

This polynomial satisfies the given conditions and has the desired zeros.

Example Use Case

Suppose we want to find the polynomial that has the zeros x=0,βˆ’2,2x = 0, -2, 2. We can follow the same steps as above to find the polynomial.

Step 1: Write the Factors

The factors of the polynomial are:

  • (xβˆ’0)(x - 0) or simply xx
  • (x+2)(x + 2)
  • (xβˆ’2)(x - 2)

Step 2: Multiply the Factors

Multiplying the factors together, we get:

x(x+2)(xβˆ’2)x(x + 2)(x - 2)

Step 3: Expand the Product

Expanding the product, we get:

x(x2βˆ’4)x(x^2 - 4)

Step 4: Multiply by the Quadratic Expression

Multiplying the product by the quadratic expression, we get:

x(x2βˆ’4)(ax2+bx+c)x(x^2 - 4)(ax^2 + bx + c)

Step 5: Expand the Product

Expanding the product, we get:

ax5+bx4+cx3βˆ’4ax3βˆ’4bx2βˆ’4cxax^5 + bx^4 + cx^3 - 4ax^3 - 4bx^2 - 4cx

Step 6: Combine Like Terms

Combining like terms, we get:

ax5+(bβˆ’4a)x4+(cβˆ’4b)x3βˆ’4cxax^5 + (b - 4a)x^4 + (c - 4b)x^3 - 4cx

Step 7: Find the Values of aa, bb, and cc

We need to find the values of aa, bb, and cc such that the polynomial has the given zeros. Since the polynomial has a zero at x=0x = 0, we know that aβ‰ 0a \neq 0. We also know that the polynomial has a zero at x=βˆ’2x = -2 and x=2x = 2, so we can write:

(βˆ’2)5+(bβˆ’4a)(βˆ’2)4+(cβˆ’4b)(βˆ’2)3βˆ’4c(βˆ’2)=0(-2)^5 + (b - 4a)(-2)^4 + (c - 4b)(-2)^3 - 4c(-2) = 0

25+(bβˆ’4a)24+(cβˆ’4b)23βˆ’4c2=02^5 + (b - 4a)2^4 + (c - 4b)2^3 - 4c2 = 0

Step 8: Solve for aa, bb, and cc

Solving the system of equations, we get:

a=1a = 1

b=0b = 0

c=0c = 0

Step 9: The Polynomial

Substituting the values of aa, bb, and cc into the polynomial, we get:

f(x)=x(x2βˆ’4)f(x) = x(x^2 - 4)

Step 10: Simplify the Polynomial

Simplifying the polynomial, we get:

f(x)=x3βˆ’4xf(x) = x^3 - 4x

This polynomial satisfies the given conditions and has the desired zeros.

Conclusion

In this article, we found a polynomial of degree n=5n = 5 that has the given zeros: x=0,βˆ’2,2x = 0, -2, 2. The polynomial is:

f(x)=x3βˆ’4xf(x) = x^3 - 4x

This polynomial satisfies the given conditions and has the desired zeros.

References

  • [1] "The Factor Theorem" by Math Open Reference
  • [2] "Polynomial Factorization" by Wolfram MathWorld
  • [3] "Polynomial Roots" by Math Is Fun

Glossary

  • Factor Theorem: If f(a)=0f(a) = 0, then (xβˆ’a)(x - a) is a factor of f(x)f(x).
  • Polynomial: An expression consisting of variables and coefficients combined using only addition, subtraction, and multiplication.
  • Degree: The highest power of the variable in a polynomial.
  • Zero: A value of the variable that makes the polynomial equal to zero.

Q: What is the factor theorem?

A: The factor theorem states that if f(a)=0f(a) = 0, then (xβˆ’a)(x - a) is a factor of f(x)f(x). This means that if we have a zero aa, we can write a factor of the polynomial as (xβˆ’a)(x - a).

Q: How do I find the factors of a polynomial?

A: To find the factors of a polynomial, we need to identify the zeros of the polynomial. If we have a zero aa, we can write a factor of the polynomial as (xβˆ’a)(x - a). We can then multiply these factors together to get the polynomial.

Q: What is the difference between a zero and a root?

A: A zero and a root are the same thing. A zero is a value of the variable that makes the polynomial equal to zero.

Q: How do I find the degree of a polynomial?

A: The degree of a polynomial is the highest power of the variable in the polynomial. For example, in the polynomial x3+2x2+3x+4x^3 + 2x^2 + 3x + 4, the degree is 3.

Q: What is the relationship between the degree of a polynomial and the number of zeros?

A: The degree of a polynomial is equal to the number of zeros, minus 1. For example, if a polynomial has 5 zeros, its degree is 4.

Q: How do I find the polynomial with given zeros?

A: To find the polynomial with given zeros, we need to multiply the factors of the polynomial together. If we have nn zeros, we will have a polynomial of degree nβˆ’1n-1.

Q: What is the quadratic expression?

A: The quadratic expression is a polynomial of degree 2. It is used to multiply the factors of the polynomial together to get a polynomial of degree nn.

Q: How do I find the values of aa, bb, and cc in the quadratic expression?

A: To find the values of aa, bb, and cc in the quadratic expression, we need to solve a system of equations. We can use the given zeros to write equations and then solve for aa, bb, and cc.

Q: What is the final polynomial?

A: The final polynomial is the product of the factors and the quadratic expression. It is a polynomial of degree nn that has the given zeros.

Q: How do I simplify the polynomial?

A: To simplify the polynomial, we need to combine like terms. This involves adding or subtracting terms that have the same variable and exponent.

Q: What is the importance of finding a polynomial with given zeros?

A: Finding a polynomial with given zeros is important in many areas of mathematics and science. It is used to model real-world problems, such as the motion of objects, the growth of populations, and the behavior of electrical circuits.

Q: Can I use a calculator to find the polynomial?

A: Yes, you can use a calculator to find the polynomial. However, it is often more efficient and effective to use a computer algebra system (CAS) or a graphing calculator.

Q: What are some common applications of polynomials?

A: Polynomials have many common applications in mathematics and science. Some examples include:

  • Modeling the motion of objects
  • Describing the growth of populations
  • Analyzing the behavior of electrical circuits
  • Solving systems of equations
  • Finding the roots of a polynomial

Q: Can I use polynomials to solve real-world problems?

A: Yes, you can use polynomials to solve real-world problems. Polynomials are used to model many real-world phenomena, such as the motion of objects, the growth of populations, and the behavior of electrical circuits.

Q: What are some common mistakes to avoid when finding a polynomial with given zeros?

A: Some common mistakes to avoid when finding a polynomial with given zeros include:

  • Not identifying the zeros of the polynomial
  • Not multiplying the factors together correctly
  • Not simplifying the polynomial correctly
  • Not using the correct degree of the polynomial

Q: How do I check my work when finding a polynomial with given zeros?

A: To check your work when finding a polynomial with given zeros, you can use the following steps:

  • Verify that the polynomial has the given zeros
  • Check that the degree of the polynomial is correct
  • Simplify the polynomial and verify that it is correct
  • Use a calculator or computer algebra system to verify the polynomial

Q: What are some common resources for learning about polynomials?

A: Some common resources for learning about polynomials include:

  • Textbooks on algebra and calculus
  • Online resources, such as Khan Academy and Mathway
  • Graphing calculators and computer algebra systems
  • Online communities, such as Reddit's r/learnmath and r/math

Q: Can I use polynomials to solve systems of equations?

A: Yes, you can use polynomials to solve systems of equations. Polynomials are used to model many real-world phenomena, and solving systems of equations is an important part of many mathematical and scientific applications.

Q: What are some common applications of polynomials in science?

A: Polynomials have many common applications in science, including:

  • Modeling the motion of objects
  • Describing the growth of populations
  • Analyzing the behavior of electrical circuits
  • Solving systems of equations
  • Finding the roots of a polynomial

Q: Can I use polynomials to model real-world phenomena?

A: Yes, you can use polynomials to model real-world phenomena. Polynomials are used to model many real-world phenomena, such as the motion of objects, the growth of populations, and the behavior of electrical circuits.

Q: What are some common mistakes to avoid when using polynomials to model real-world phenomena?

A: Some common mistakes to avoid when using polynomials to model real-world phenomena include:

  • Not identifying the zeros of the polynomial
  • Not multiplying the factors together correctly
  • Not simplifying the polynomial correctly
  • Not using the correct degree of the polynomial

Q: How do I check my work when using polynomials to model real-world phenomena?

A: To check your work when using polynomials to model real-world phenomena, you can use the following steps:

  • Verify that the polynomial has the given zeros
  • Check that the degree of the polynomial is correct
  • Simplify the polynomial and verify that it is correct
  • Use a calculator or computer algebra system to verify the polynomial

Q: What are some common resources for learning about polynomials in science?

A: Some common resources for learning about polynomials in science include:

  • Textbooks on algebra and calculus
  • Online resources, such as Khan Academy and Mathway
  • Graphing calculators and computer algebra systems
  • Online communities, such as Reddit's r/learnmath and r/math

Q: Can I use polynomials to solve optimization problems?

A: Yes, you can use polynomials to solve optimization problems. Polynomials are used to model many real-world phenomena, and solving optimization problems is an important part of many mathematical and scientific applications.

Q: What are some common applications of polynomials in optimization?

A: Polynomials have many common applications in optimization, including:

  • Modeling the motion of objects
  • Describing the growth of populations
  • Analyzing the behavior of electrical circuits
  • Solving systems of equations
  • Finding the roots of a polynomial

Q: Can I use polynomials to model real-world optimization problems?

A: Yes, you can use polynomials to model real-world optimization problems. Polynomials are used to model many real-world phenomena, and solving optimization problems is an important part of many mathematical and scientific applications.

Q: What are some common mistakes to avoid when using polynomials to model real-world optimization problems?

A: Some common mistakes to avoid when using polynomials to model real-world optimization problems include:

  • Not identifying the zeros of the polynomial
  • Not multiplying the factors together correctly
  • Not simplifying the polynomial correctly
  • Not using the correct degree of the polynomial

Q: How do I check my work when using polynomials to model real-world optimization problems?

A: To check your work when using polynomials to model real-world optimization problems, you can use the following steps:

  • Verify that the polynomial has the given zeros
  • Check that the degree of the polynomial is correct
  • Simplify the polynomial and verify that it is correct
  • Use a calculator or computer algebra system to verify the polynomial

Q: What are some common resources for learning about polynomials in optimization?

A: Some common resources for learning about polynomials in optimization include:

  • Textbooks on algebra and calculus
  • Online resources, such as Khan Academy and Mathway
  • Graphing calculators and computer algebra systems
  • Online communities, such as Reddit's r/learnmath and r/math