Students Were Asked To Write $6 X^5+8 X-3 X^3+7 X^7$ In Standard Form. Shown Below Are Four Student Responses.Anne: $7 X^7+6 X^5-3 X^3+8 X$Bob: $-3 X^3+6 X^5+7 X^7+8 X$Carrie: $8 X+7 X^7+6 X^5-3 X^3$Dylan: $8

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Understanding the Concept of Standard Form

In mathematics, polynomials are expressions consisting of variables and coefficients combined using only addition, subtraction, and multiplication. When it comes to writing polynomials in standard form, students often struggle to arrange the terms in the correct order. In this article, we will explore the concept of standard form and provide guidance on how to write polynomials in this format.

What is Standard Form?

Standard form, also known as descending order, is a way of writing polynomials where the terms are arranged in decreasing order of their exponents. This means that the term with the highest exponent comes first, followed by the term with the next highest exponent, and so on. For example, the polynomial 6x5+8xβˆ’3x3+7x76x^5 + 8x - 3x^3 + 7x^7 can be written in standard form as 7x7+6x5βˆ’3x3+8x7x^7 + 6x^5 - 3x^3 + 8x.

Analyzing Student Responses

Let's take a look at the responses from Anne, Bob, Carrie, and Dylan:

  • Anne: 7x7+6x5βˆ’3x3+8x7x^7 + 6x^5 - 3x^3 + 8x
  • Bob: βˆ’3x3+6x5+7x7+8x-3x^3 + 6x^5 + 7x^7 + 8x
  • Carrie: 8x+7x7+6x5βˆ’3x38x + 7x^7 + 6x^5 - 3x^3
  • Dylan: 8xβˆ’3x3+6x5+7x78x - 3x^3 + 6x^5 + 7x^7

Evaluating the Correctness of Each Response

To determine which response is correct, we need to examine each term and its corresponding exponent.

  • Anne's Response: 7x7+6x5βˆ’3x3+8x7x^7 + 6x^5 - 3x^3 + 8x
    • The term with the highest exponent is 7x77x^7.
    • The term with the next highest exponent is 6x56x^5.
    • The term with the next highest exponent is βˆ’3x3-3x^3.
    • The term with the lowest exponent is 8x8x.
    • Correct!
  • Bob's Response: βˆ’3x3+6x5+7x7+8x-3x^3 + 6x^5 + 7x^7 + 8x
    • The term with the highest exponent is 7x77x^7.
    • The term with the next highest exponent is 6x56x^5.
    • The term with the next highest exponent is βˆ’3x3-3x^3.
    • The term with the lowest exponent is 8x8x.
    • Incorrect. The term βˆ’3x3-3x^3 should come before the term 6x56x^5.
  • Carrie's Response: 8x+7x7+6x5βˆ’3x38x + 7x^7 + 6x^5 - 3x^3
    • The term with the highest exponent is 7x77x^7.
    • The term with the next highest exponent is 6x56x^5.
    • The term with the next highest exponent is βˆ’3x3-3x^3.
    • The term with the lowest exponent is 8x8x.
    • Incorrect. The term 8x8x should come before the term 7x77x^7.
  • Dylan's Response: 8xβˆ’3x3+6x5+7x78x - 3x^3 + 6x^5 + 7x^7
    • The term with the highest exponent is 7x77x^7.
    • The term with the next highest exponent is 6x56x^5.
    • The term with the next highest exponent is βˆ’3x3-3x^3.
    • The term with the lowest exponent is 8x8x.
    • Incorrect. The term 8x8x should come before the term βˆ’3x3-3x^3.

Conclusion

In conclusion, the correct response is Anne's: 7x7+6x5βˆ’3x3+8x7x^7 + 6x^5 - 3x^3 + 8x. This is because the terms are arranged in decreasing order of their exponents, with the term with the highest exponent coming first. The other responses, while close, contain errors in the arrangement of the terms.

Tips for Writing Polynomials in Standard Form

To write polynomials in standard form, follow these steps:

  1. Identify the terms: Break down the polynomial into individual terms.
  2. Arrange the terms: Arrange the terms in decreasing order of their exponents.
  3. Check for errors: Double-check that the terms are in the correct order.

By following these steps, you can ensure that your polynomial is written in standard form.

Common Mistakes to Avoid

When writing polynomials in standard form, be careful not to make the following mistakes:

  • Incorrect order: Make sure the terms are in decreasing order of their exponents.
  • Missing terms: Ensure that all terms are included in the polynomial.
  • Extra terms: Avoid adding extra terms that are not part of the original polynomial.

By being aware of these common mistakes, you can avoid errors and write polynomials in standard form with confidence.

Practice Exercises

To practice writing polynomials in standard form, try the following exercises:

  1. Exercise 1: Write the polynomial 2x4+3x2βˆ’4x+12x^4 + 3x^2 - 4x + 1 in standard form.
  2. Exercise 2: Write the polynomial x3βˆ’2x2+3xβˆ’1x^3 - 2x^2 + 3x - 1 in standard form.
  3. Exercise 3: Write the polynomial 4x2+2xβˆ’34x^2 + 2x - 3 in standard form.

By practicing these exercises, you can improve your skills in writing polynomials in standard form.

Conclusion

Frequently Asked Questions

Q: What is standard form in polynomials?

A: Standard form, also known as descending order, is a way of writing polynomials where the terms are arranged in decreasing order of their exponents. This means that the term with the highest exponent comes first, followed by the term with the next highest exponent, and so on.

Q: How do I write a polynomial in standard form?

A: To write a polynomial in standard form, follow these steps:

  1. Identify the terms: Break down the polynomial into individual terms.
  2. Arrange the terms: Arrange the terms in decreasing order of their exponents.
  3. Check for errors: Double-check that the terms are in the correct order.

Q: What are some common mistakes to avoid when writing polynomials in standard form?

A: When writing polynomials in standard form, be careful not to make the following mistakes:

  • Incorrect order: Make sure the terms are in decreasing order of their exponents.
  • Missing terms: Ensure that all terms are included in the polynomial.
  • Extra terms: Avoid adding extra terms that are not part of the original polynomial.

Q: How do I check if a polynomial is written in standard form?

A: To check if a polynomial is written in standard form, follow these steps:

  1. Identify the terms: Break down the polynomial into individual terms.
  2. Check the order: Ensure that the terms are in decreasing order of their exponents.
  3. Check for errors: Double-check that the terms are in the correct order.

Q: Can you provide some examples of polynomials written in standard form?

A: Here are some examples of polynomials written in standard form:

  • Example 1: 7x7+6x5βˆ’3x3+8x7x^7 + 6x^5 - 3x^3 + 8x
  • Example 2: 2x4+3x2βˆ’4x+12x^4 + 3x^2 - 4x + 1
  • Example 3: x3βˆ’2x2+3xβˆ’1x^3 - 2x^2 + 3x - 1

Q: How do I practice writing polynomials in standard form?

A: To practice writing polynomials in standard form, try the following exercises:

  1. Exercise 1: Write the polynomial 2x4+3x2βˆ’4x+12x^4 + 3x^2 - 4x + 1 in standard form.
  2. Exercise 2: Write the polynomial x3βˆ’2x2+3xβˆ’1x^3 - 2x^2 + 3x - 1 in standard form.
  3. Exercise 3: Write the polynomial 4x2+2xβˆ’34x^2 + 2x - 3 in standard form.

Q: What are some real-world applications of writing polynomials in standard form?

A: Writing polynomials in standard form has many real-world applications, including:

  • Science: In science, polynomials are used to model real-world phenomena, such as the motion of objects or the growth of populations.
  • Engineering: In engineering, polynomials are used to design and optimize systems, such as bridges or electronic circuits.
  • Economics: In economics, polynomials are used to model economic systems and make predictions about future trends.

Conclusion

In conclusion, writing polynomials in standard form is an essential skill in mathematics. By following the steps outlined in this article, you can ensure that your polynomials are written in the correct format. Remember to be careful when arranging the terms and to avoid common mistakes. With practice, you can become proficient in writing polynomials in standard form.