Select All The Expressions That Are Equivalent To $5^3 \cdot 5^{-4}$.A. $\frac{1}{5^{-12}}$ B. $\frac{1}{5^{-1}}$ C. $5^{-1}$ D. $\frac{1}{5}$

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Introduction

Exponential expressions are a fundamental concept in mathematics, and understanding how to simplify them is crucial for solving various mathematical problems. In this article, we will focus on simplifying the expression 53β‹…5βˆ’45^3 \cdot 5^{-4} and identifying equivalent forms.

Understanding Exponents

Before we dive into simplifying the expression, let's briefly review the concept of exponents. An exponent is a small number that is written above and to the right of a base number. It represents the number of times the base number is multiplied by itself. For example, 535^3 means 55 multiplied by itself 33 times, which is equal to 5β‹…5β‹…5=1255 \cdot 5 \cdot 5 = 125.

Simplifying the Expression

Now, let's simplify the expression 53β‹…5βˆ’45^3 \cdot 5^{-4}. To do this, we can use the rule of exponents that states when multiplying two numbers with the same base, we add their exponents. In this case, the base is 55, and the exponents are 33 and βˆ’4-4. Therefore, we can simplify the expression as follows:

53β‹…5βˆ’4=53+(βˆ’4)=5βˆ’15^3 \cdot 5^{-4} = 5^{3 + (-4)} = 5^{-1}

Equivalent Forms

Now that we have simplified the expression to 5βˆ’15^{-1}, let's explore equivalent forms. An equivalent form is an expression that has the same value as the original expression. In this case, we can rewrite 5βˆ’15^{-1} in several equivalent forms:

  • Fractional form: We can rewrite 5βˆ’15^{-1} as a fraction by using the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. Therefore, 5βˆ’1=151=155^{-1} = \frac{1}{5^1} = \frac{1}{5}.
  • Negative exponent form: We can also rewrite 5βˆ’15^{-1} using a negative exponent. Since aβˆ’n=1ana^{-n} = \frac{1}{a^n}, we can rewrite 5βˆ’15^{-1} as 151=15\frac{1}{5^1} = \frac{1}{5}.
  • Inverse form: Finally, we can rewrite 5βˆ’15^{-1} as an inverse form by using the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. Therefore, 5βˆ’1=151=155^{-1} = \frac{1}{5^1} = \frac{1}{5}.

Conclusion

In conclusion, we have simplified the expression 53β‹…5βˆ’45^3 \cdot 5^{-4} to 5βˆ’15^{-1} and explored equivalent forms. We have shown that 5βˆ’15^{-1} can be rewritten in several equivalent forms, including fractional form, negative exponent form, and inverse form. These equivalent forms are useful for solving various mathematical problems and can help us to simplify complex expressions.

Answer

Based on our analysis, we can conclude that the correct answer is:

  • D. 15\frac{1}{5}

This is because 15\frac{1}{5} is an equivalent form of 5βˆ’15^{-1}, which is the simplified expression of 53β‹…5βˆ’45^3 \cdot 5^{-4}.

Discussion

Now that we have simplified the expression and identified equivalent forms, let's discuss some related topics.

  • Exponent rules: We have used several exponent rules to simplify the expression, including the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n} and the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}. These rules are essential for simplifying exponential expressions and are used extensively in mathematics.
  • Equivalent forms: We have shown that 5βˆ’15^{-1} can be rewritten in several equivalent forms, including fractional form, negative exponent form, and inverse form. These equivalent forms are useful for solving various mathematical problems and can help us to simplify complex expressions.
  • Simplifying expressions: We have simplified the expression 53β‹…5βˆ’45^3 \cdot 5^{-4} to 5βˆ’15^{-1} using exponent rules. This process involves applying the rules of exponents to simplify the expression and identify equivalent forms.

Practice Problems

Now that we have simplified the expression and identified equivalent forms, let's practice solving some related problems.

  • Problem 1: Simplify the expression 24β‹…2βˆ’32^4 \cdot 2^{-3}.
  • Problem 2: Rewrite the expression 3βˆ’23^{-2} in fractional form.
  • Problem 3: Simplify the expression 42β‹…4βˆ’14^2 \cdot 4^{-1}.

Solution

  • Problem 1: Using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}, we can simplify the expression as follows: 24β‹…2βˆ’3=24+(βˆ’3)=21=22^4 \cdot 2^{-3} = 2^{4 + (-3)} = 2^1 = 2.
  • Problem 2: Using the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}, we can rewrite the expression as follows: 3βˆ’2=132=193^{-2} = \frac{1}{3^2} = \frac{1}{9}.
  • Problem 3: Using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}, we can simplify the expression as follows: 42β‹…4βˆ’1=42+(βˆ’1)=41=44^2 \cdot 4^{-1} = 4^{2 + (-1)} = 4^1 = 4.

Conclusion

Q: What is the rule for simplifying exponential expressions?

A: The rule for simplifying exponential expressions is to use the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}.

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

A: To simplify an expression with a negative exponent, you can use the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. For example, 5βˆ’1=151=155^{-1} = \frac{1}{5^1} = \frac{1}{5}.

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

A: A positive exponent means that the base number is being multiplied by itself a certain number of times, while a negative exponent means that the base number is being divided by itself a certain number of times.

Q: How do I rewrite an expression with a negative exponent in fractional form?

A: To rewrite an expression with a negative exponent in fractional form, you can use the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. For example, 3βˆ’2=132=193^{-2} = \frac{1}{3^2} = \frac{1}{9}.

Q: What is the inverse form of an expression with a negative exponent?

A: The inverse form of an expression with a negative exponent is the same as the fractional form. For example, 5βˆ’1=155^{-1} = \frac{1}{5}.

Q: Can I simplify an expression with a negative exponent by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}?

A: No, you cannot simplify an expression with a negative exponent by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}. This rule only applies to expressions with positive exponents.

Q: How do I simplify an expression with multiple negative exponents?

A: To simplify an expression with multiple negative exponents, you can use the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n} and the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}. For example, 5βˆ’3β‹…5βˆ’2=5(βˆ’3)+(βˆ’2)=5βˆ’5=155=131255^{-3} \cdot 5^{-2} = 5^{(-3) + (-2)} = 5^{-5} = \frac{1}{5^5} = \frac{1}{3125}.

Q: Can I simplify an expression with a negative exponent by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and then taking the reciprocal of the result?

A: Yes, you can simplify an expression with a negative exponent by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and then taking the reciprocal of the result. For example, 5βˆ’3β‹…5βˆ’2=5(βˆ’3)+(βˆ’2)=5βˆ’5=155=131255^{-3} \cdot 5^{-2} = 5^{(-3) + (-2)} = 5^{-5} = \frac{1}{5^5} = \frac{1}{3125}.

Q: How do I know when to use the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n} and when to use the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n}?

A: You should use the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n} when you have an expression with a negative exponent, and you should use the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} when you have an expression with multiple positive exponents.

Q: Can I simplify an expression with a negative exponent by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and then taking the reciprocal of the result, even if the expression has multiple negative exponents?

A: Yes, you can simplify an expression with multiple negative exponents by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and then taking the reciprocal of the result. For example, 5βˆ’3β‹…5βˆ’2=5(βˆ’3)+(βˆ’2)=5βˆ’5=155=131255^{-3} \cdot 5^{-2} = 5^{(-3) + (-2)} = 5^{-5} = \frac{1}{5^5} = \frac{1}{3125}.

Conclusion

In conclusion, we have answered some common questions about simplifying exponential expressions. We have shown that the rule for simplifying exponential expressions is to use the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n}. We have also shown that you can simplify an expression with a negative exponent by using the rule that aβˆ’n=1ana^{-n} = \frac{1}{a^n} and that you can simplify an expression with multiple negative exponents by using the rule that amβ‹…an=am+na^m \cdot a^n = a^{m+n} and then taking the reciprocal of the result.