Write The Following Expression Without Negative Exponents And Without Parentheses:$-5x^{-2}$

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Understanding Negative Exponents

In algebra, negative exponents are a way to represent very small numbers or fractions. When we see a negative exponent, it means that the base is being raised to a power that is the negative of the given exponent. In other words, a negative exponent is equivalent to taking the reciprocal of the base raised to the positive exponent.

Rewriting Negative Exponents

To rewrite an expression with a negative exponent without parentheses, we can use the rule that states:

a−n=1ana^{-n} = \frac{1}{a^n}

This means that we can move the negative exponent to the other side of the fraction bar and change its sign.

Applying the Rule to the Given Expression

Let's apply this rule to the given expression:

−5x−2-5x^{-2}

Using the rule, we can rewrite the expression as:

−5⋅1x2-5 \cdot \frac{1}{x^2}

Simplifying the Expression

Now, we can simplify the expression by multiplying the coefficient (-5) with the fraction:

−5⋅1x2=−5x2-5 \cdot \frac{1}{x^2} = -\frac{5}{x^2}

Conclusion

In this article, we learned how to simplify an algebraic expression with a negative exponent without parentheses. We used the rule that states a negative exponent is equivalent to taking the reciprocal of the base raised to the positive exponent. By applying this rule, we were able to rewrite the given expression and simplify it to its final form.

Examples and Practice

Here are a few examples of expressions with negative exponents that we can simplify using the same rule:

  • 2x−3=2x32x^{-3} = \frac{2}{x^3}
  • −3y−2=−3y2-3y^{-2} = -\frac{3}{y^2}
  • 4z−1=4z4z^{-1} = \frac{4}{z}

Tips and Tricks

When working with negative exponents, it's essential to remember that they represent very small numbers or fractions. To simplify expressions with negative exponents, we can use the rule that states a negative exponent is equivalent to taking the reciprocal of the base raised to the positive exponent.

Common Mistakes to Avoid

When simplifying expressions with negative exponents, it's easy to make mistakes. Here are a few common mistakes to avoid:

  • Not using the correct rule for negative exponents
  • Not simplifying the expression correctly
  • Not checking the final answer for errors

Real-World Applications

Negative exponents have many real-world applications in fields such as physics, engineering, and economics. For example, in physics, negative exponents can be used to represent the decay of radioactive materials. In engineering, negative exponents can be used to represent the attenuation of signals in electrical circuits.

Conclusion

Q: What is a negative exponent?

A: A negative exponent is a way to represent very small numbers or fractions. When we see a negative exponent, it means that the base is being raised to a power that is the negative of the given exponent.

Q: How do I simplify an expression with a negative exponent?

A: To simplify an expression with a negative exponent, we can use the rule that states:

a−n=1ana^{-n} = \frac{1}{a^n}

This means that we can move the negative exponent to the other side of the fraction bar and change its sign.

Q: What is the difference between a negative exponent and a fraction?

A: A negative exponent and a fraction are not the same thing, although they can be equivalent. A negative exponent represents a very small number or fraction, while a fraction represents a ratio of two numbers.

Q: Can I simplify an expression with a negative exponent by multiplying it by a fraction?

A: No, you cannot simplify an expression with a negative exponent by multiplying it by a fraction. To simplify an expression with a negative exponent, you must use the rule that states:

a−n=1ana^{-n} = \frac{1}{a^n}

Q: How do I handle negative exponents with variables?

A: When working with negative exponents and variables, we can use the same rule as before:

x−n=1xnx^{-n} = \frac{1}{x^n}

For example, if we have the expression x−2x^{-2}, we can simplify it as:

x−2=1x2x^{-2} = \frac{1}{x^2}

Q: Can I simplify an expression with a negative exponent by using a calculator?

A: Yes, you can simplify an expression with a negative exponent by using a calculator. However, it's essential to understand the underlying math behind the calculation to ensure that you're getting the correct answer.

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

A: Some common mistakes to avoid when simplifying negative exponents include:

  • Not using the correct rule for negative exponents
  • Not simplifying the expression correctly
  • Not checking the final answer for errors

Q: How do I know if an expression has a negative exponent?

A: An expression has a negative exponent if it contains a variable or constant raised to a power that is negative. For example, the expression x−2x^{-2} has a negative exponent because the variable xx is raised to a power of -2.

Q: Can I simplify an expression with a negative exponent by using algebraic manipulations?

A: Yes, you can simplify an expression with a negative exponent by using algebraic manipulations such as factoring, combining like terms, and canceling out common factors.

Q: What are some real-world applications of negative exponents?

A: Negative exponents have many real-world applications in fields such as physics, engineering, and economics. For example, in physics, negative exponents can be used to represent the decay of radioactive materials. In engineering, negative exponents can be used to represent the attenuation of signals in electrical circuits.

Conclusion

In conclusion, simplifying expressions with negative exponents is a crucial skill in algebra. By using the rule that states a negative exponent is equivalent to taking the reciprocal of the base raised to the positive exponent, we can rewrite expressions without parentheses and simplify them to their final form. With practice and patience, you can master this skill and become proficient in simplifying expressions with negative exponents.