Does The Expression X 3 − 1 X 2 − 1 \frac{x^3-1}{x^2-1} X 2 − 1 X 3 − 1 ​ Simplify To X X X ?A. No, Because X 3 − 1 X^3-1 X 3 − 1 Can Be Factored As X ( X 2 − X + 1 X(x^2-x+1 X ( X 2 − X + 1 ] And X 2 − 1 X^2-1 X 2 − 1 Can Be Factored As X ( X − 1 X(x-1 X ( X − 1 ], So Only X X X Can Be Canceled.B. Yes,

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Does the Expression x31x21\frac{x^3-1}{x^2-1} Simplify to xx?

Understanding the Problem

The given expression is x31x21\frac{x^3-1}{x^2-1}, and we are asked to determine whether it simplifies to xx. To approach this problem, we need to carefully analyze the numerator and denominator of the expression.

Factoring the Numerator and Denominator

The numerator x31x^3-1 can be factored using the difference of cubes formula: a3b3=(ab)(a2+ab+b2)a^3-b^3 = (a-b)(a^2+ab+b^2). In this case, we have a=xa = x and b=1b = 1, so we can write:

x31=(x1)(x2+x+1)x^3-1 = (x-1)(x^2+x+1)

Similarly, the denominator x21x^2-1 can be factored as:

x21=(x1)(x+1)x^2-1 = (x-1)(x+1)

Canceling Common Factors

Now that we have factored the numerator and denominator, we can see that both expressions have a common factor of (x1)(x-1). This means that we can cancel out the (x1)(x-1) terms, leaving us with:

(x1)(x2+x+1)(x1)(x+1)\frac{(x-1)(x^2+x+1)}{(x-1)(x+1)}

Simplifying the Expression

After canceling the common factor, we are left with:

x2+x+1x+1\frac{x^2+x+1}{x+1}

This is the simplified expression, but it is not equal to xx. Therefore, the correct answer is:

A. No, because x31x^3-1 can be factored as x(x2x+1)x(x^2-x+1) and x21x^2-1 can be factored as x(x1)x(x-1), so only xx can be canceled.

Why the Simplification is Incorrect

The reason why the simplification to xx is incorrect is that it relies on canceling the (x1)(x-1) term, which is not valid. When we cancel a term, we are essentially assuming that the term is not equal to zero. However, in this case, the term (x1)(x-1) can be equal to zero, which means that the expression is not defined for x=1x = 1. Therefore, we cannot simply cancel the (x1)(x-1) term and expect the expression to simplify to xx.

Conclusion

In conclusion, the expression x31x21\frac{x^3-1}{x^2-1} does not simplify to xx. The correct simplification is x2+x+1x+1\frac{x^2+x+1}{x+1}, which is a different expression altogether. This highlights the importance of carefully analyzing the numerator and denominator of an expression before attempting to simplify it.

Common Mistakes to Avoid

When simplifying expressions, it is easy to make mistakes. Here are some common mistakes to avoid:

  • Canceling common factors without checking for zero: Make sure to check if the common factor is equal to zero before canceling it.
  • Not considering the domain of the expression: Make sure to consider the domain of the expression and check if it is defined for all possible values of xx.
  • Not simplifying the expression correctly: Make sure to simplify the expression correctly by following the rules of algebra.

Real-World Applications

Simplifying expressions is an important skill in mathematics, and it has many real-world applications. For example:

  • Engineering: Simplifying expressions is crucial in engineering, where complex mathematical models are used to design and analyze systems.
  • Physics: Simplifying expressions is essential in physics, where mathematical models are used to describe the behavior of physical systems.
  • Computer Science: Simplifying expressions is important in computer science, where mathematical models are used to analyze and optimize algorithms.

Final Thoughts

In conclusion, the expression x31x21\frac{x^3-1}{x^2-1} does not simplify to xx. The correct simplification is x2+x+1x+1\frac{x^2+x+1}{x+1}, which is a different expression altogether. This highlights the importance of carefully analyzing the numerator and denominator of an expression before attempting to simplify it. By following the rules of algebra and considering the domain of the expression, we can ensure that our simplifications are correct and accurate.
Q&A: Simplifying Expressions

Frequently Asked Questions

In this article, we will answer some frequently asked questions about simplifying expressions. Whether you are a student, a teacher, or a professional, you will find these questions and answers helpful in understanding the basics of simplifying expressions.

Q: What is simplifying an expression?

A: Simplifying an expression means rewriting it in a more compact and easier-to-understand form, while still maintaining its original value. This involves combining like terms, canceling out common factors, and rearranging the expression to make it more manageable.

Q: Why is simplifying expressions important?

A: Simplifying expressions is important because it helps us to:

  • Understand complex mathematical concepts: By simplifying expressions, we can gain a deeper understanding of complex mathematical concepts and relationships.
  • Solve problems more efficiently: Simplifying expressions can help us to solve problems more efficiently, as we can work with a more manageable and compact form of the expression.
  • Communicate mathematical ideas effectively: Simplifying expressions can help us to communicate mathematical ideas more effectively, as we can present complex concepts in a more concise and clear manner.

Q: What are some common mistakes to avoid when simplifying expressions?

A: Some common mistakes to avoid when simplifying expressions include:

  • Canceling common factors without checking for zero: Make sure to check if the common factor is equal to zero before canceling it.
  • Not considering the domain of the expression: Make sure to consider the domain of the expression and check if it is defined for all possible values of xx.
  • Not simplifying the expression correctly: Make sure to simplify the expression correctly by following the rules of algebra.

Q: How do I simplify a complex expression?

A: To simplify a complex expression, follow these steps:

  1. Identify like terms: Identify like terms in the expression and combine them.
  2. Cancel out common factors: Cancel out common factors in the expression, but make sure to check if the common factor is equal to zero.
  3. Rearrange the expression: Rearrange the expression to make it more manageable and compact.
  4. Check the domain: Check the domain of the expression and make sure it is defined for all possible values of xx.

Q: What are some real-world applications of simplifying expressions?

A: Simplifying expressions has many real-world applications, including:

  • Engineering: Simplifying expressions is crucial in engineering, where complex mathematical models are used to design and analyze systems.
  • Physics: Simplifying expressions is essential in physics, where mathematical models are used to describe the behavior of physical systems.
  • Computer Science: Simplifying expressions is important in computer science, where mathematical models are used to analyze and optimize algorithms.

Q: Can I use technology to simplify expressions?

A: Yes, you can use technology to simplify expressions. Many calculators and computer algebra systems (CAS) can simplify expressions automatically, making it easier to work with complex mathematical concepts.

Q: How do I know if an expression is simplified correctly?

A: To know if an expression is simplified correctly, follow these steps:

  1. Check the expression for errors: Check the expression for errors, such as incorrect cancellations or rearrangements.
  2. Verify the expression: Verify the expression by plugging in values for xx and checking if the expression evaluates to the correct value.
  3. Check the domain: Check the domain of the expression and make sure it is defined for all possible values of xx.

Conclusion

In conclusion, simplifying expressions is an important skill in mathematics, and it has many real-world applications. By following the rules of algebra and considering the domain of the expression, we can ensure that our simplifications are correct and accurate. Whether you are a student, a teacher, or a professional, you will find these questions and answers helpful in understanding the basics of simplifying expressions.