Applying the Rule for Negative Exponents

Oct 13, 2025 by wbrum.org 86 views

Understanding the Problem

When dealing with exponents, it's essential to understand the rules and properties that govern them. In this case, we're given the expression $\left(\frac{8}{27}\right)^{-\frac{2}{3}}$ , and we're asked to simplify it. To start, let's recall the rule for negative exponents: $a^{-n} = \frac{1}{a^n}$ . This means that when we have a negative exponent, we can rewrite it as a positive exponent by taking the reciprocal of the base.

Applying the Rule for Negative Exponents

Using the rule for negative exponents, we can rewrite the given expression as:

\left(\frac{8}{27}\right)^{-\frac{2}{3}} = \frac{1}{\left(\frac{8}{27}\right)^{\frac{2}{3}}}

Simplifying the Expression

Now, let's focus on simplifying the expression inside the parentheses. To do this, we'll use the rule for rational exponents: $\left(\frac{a}{b}\right)^n = \frac{a^n}{b^n}$ . This means that when we have a rational exponent, we can rewrite it as a fraction of two powers.

Applying the Rule for Rational Exponents

Using the rule for rational exponents, we can rewrite the expression inside the parentheses as:

\left(\frac{8}{27}\right)^{\frac{2}{3}} = \frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}

Simplifying the Powers

Now, let's focus on simplifying the powers. To do this, we'll use the rule for fractional exponents: $a^{\frac{m}{n}} = \sqrt[n]{a^m}$ . This means that when we have a fractional exponent, we can rewrite it as a root of a power.

Applying the Rule for Fractional Exponents

Using the rule for fractional exponents, we can rewrite the powers as:

8^{\frac{2}{3}} = \sqrt[3]{8^2}

27^{\frac{2}{3}} = \sqrt[3]{27^2}

Simplifying the Roots

Now, let's focus on simplifying the roots. To do this, we'll use the rule for roots: $\sqrt[n]{a^m} = (a^m)^{\frac{1}{n}}$ . This means that when we have a root, we can rewrite it as a power of a power.

Applying the Rule for Roots

Using the rule for roots, we can rewrite the roots as:

\sqrt[3]{8^2} = (8^2)^{\frac{1}{3}}

\sqrt[3]{27^2} = (27^2)^{\frac{1}{3}}

Simplifying the Powers of Powers

Now, let's focus on simplifying the powers of powers. To do this, we'll use the rule for powers of powers: $(a^m)^n = a^{mn}$ . This means that when we have a power of a power, we can rewrite it as a single power.

Applying the Rule for Powers of Powers

Using the rule for powers of powers, we can rewrite the powers of powers as:

(8^2)^{\frac{1}{3}} = 8^{\frac{2}{3}}

(27^2)^{\frac{1}{3}} = 27^{\frac{2}{3}}

Simplifying the Expression

Now, let's focus on simplifying the expression. To do this, we'll substitute the simplified powers back into the original expression.

\frac{1}{\left(\frac{8}{27}\right)^{\frac{2}{3}}} = \frac{1}{\frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}}

Canceling Out the Powers

Now, let's focus on canceling out the powers. To do this, we'll use the rule for dividing fractions: $\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \cdot \frac{d}{c}$ . This means that when we divide fractions, we can rewrite it as a product of fractions.

Applying the Rule for Dividing Fractions

Using the rule for dividing fractions, we can rewrite the expression as:

\frac{1}{\frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}} = \frac{1}{\frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}} \cdot \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}}

Canceling Out the Powers

Now, let's focus on canceling out the powers. To do this, we'll use the rule for canceling out powers: $\frac{a^m}{a^n} = a^{m-n}$ . This means that when we have a power of a power, we can rewrite it as a single power.

Applying the Rule for Canceling Out Powers

Using the rule for canceling out powers, we can rewrite the expression as:

\frac{1}{\frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}} \cdot \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}} = \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}} \cdot \frac{1}{1}

Simplifying the Expression

Now, let's focus on simplifying the expression. To do this, we'll use the rule for multiplying fractions: $\frac{a}{b} \cdot \frac{c}{d} = \frac{ac}{bd}$ . This means that when we multiply fractions, we can rewrite it as a single fraction.

Applying the Rule for Multiplying Fractions

Using the rule for multiplying fractions, we can rewrite the expression as:

\frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}} \cdot \frac{1}{1} = \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}}

Simplifying the Expression

Now, let's focus on simplifying the expression. To do this, we'll use the rule for simplifying fractions: $\frac{a}{b} = \frac{c}{d} \iff a \cdot d = b \cdot c$ . This means that when we have a fraction, we can rewrite it as a product of two numbers.

Applying the Rule for Simplifying Fractions

Using the rule for simplifying fractions, we can rewrite the expression as:

\frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}} = \frac{\sqrt[3]{27^2}}{\sqrt[3]{8^2}}

Simplifying the Roots

Applying the Rule for Roots

Using the rule for roots, we can rewrite the roots as:

\sqrt[3]{27^2} = (27^2)^{\frac{1}{3}}

\sqrt[3]{8^2} = (8^2)^{\frac{1}{3}}

Simplifying the Powers of Powers

Applying the Rule for Powers of Powers

Using the rule for powers of powers, we can rewrite the powers of powers as:

(27^2)^{\frac{1}{3}} = 27^{\frac{2}{3}}

(8^2)^{\frac{1}{3}} = 8^{\frac{2}{3}}

Simplifying the Expression

Now, let's focus on simplifying the expression. To do this, we'll substitute the simplified powers back into the original expression.

\frac{\sqrt[3]{27^2}}{\sqrt[3]{8^2}} = \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}}

Simplifying the Expression

Applying the Rule for Simplifying Fractions

Using the rule for simplifying fractions, we can rewrite the expression as:

\frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}} = \<br/> # Simplify: $\left(\frac{8}{27}\right)^{-\frac{2}{3}}$ - Q&A

Understanding the Problem

Q&A

Q: What is the rule for negative exponents?

A: The rule for negative exponents is $a^{-n} = \frac{1}{a^n}$ . This means that when we have a negative exponent, we can rewrite it as a positive exponent by taking the reciprocal of the base.

Q: How do we simplify the expression $\left(\frac{8}{27}\right)^{-\frac{2}{3}}$ ?

A: To simplify the expression, we'll use the rule for negative exponents. We can rewrite the expression as $\frac{1}{\left(\frac{8}{27}\right)^{\frac{2}{3}}}$ .

Q: How do we simplify the expression inside the parentheses?

A: To simplify the expression inside the parentheses, we'll use the rule for rational exponents: $\left(\frac{a}{b}\right)^n = \frac{a^n}{b^n}$ . This means that when we have a rational exponent, we can rewrite it as a fraction of two powers.

Q: How do we simplify the powers?

A: To simplify the powers, we'll use the rule for fractional exponents: $a^{\frac{m}{n}} = \sqrt[n]{a^m}$ . This means that when we have a fractional exponent, we can rewrite it as a root of a power.

Q: How do we simplify the roots?

A: To simplify the roots, we'll use the rule for roots: $\sqrt[n]{a^m} = (a^m)^{\frac{1}{n}}$ . This means that when we have a root, we can rewrite it as a power of a power.

Q: How do we simplify the powers of powers?

A: To simplify the powers of powers, we'll use the rule for powers of powers: $(a^m)^n = a^{mn}$ . This means that when we have a power of a power, we can rewrite it as a single power.

Q: How do we simplify the expression?

A: To simplify the expression, we'll substitute the simplified powers back into the original expression.

Example

Let's use the expression $\left(\frac{8}{27}\right)^{-\frac{2}{3}}$ as an example. We can simplify it by following the steps outlined above.

Step 1: Simplify the expression inside the parentheses

$\left(\frac{8}{27}\right)^{\frac{2}{3}} = \frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}$

Step 2: Simplify the powers

$8^{\frac{2}{3}} = \sqrt[3]{8^2}$

$27^{\frac{2}{3}} = \sqrt[3]{27^2}$

Step 3: Simplify the roots

$\sqrt[3]{8^2} = (8^2)^{\frac{1}{3}}$

$\sqrt[3]{27^2} = (27^2)^{\frac{1}{3}}$

Step 4: Simplify the powers of powers

$(8^2)^{\frac{1}{3}} = 8^{\frac{2}{3}}$

$(27^2)^{\frac{1}{3}} = 27^{\frac{2}{3}}$

Step 5: Simplify the expression

$\frac{1}{\left(\frac{8}{27}\right)^{\frac{2}{3}}} = \frac{1}{\frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}}$

Step 6: Cancel out the powers

$\frac{1}{\frac{8^{\frac{2}{3}}}{27^{\frac{2}{3}}}} = \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}}$

Step 7: Simplify the expression

$\frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}} = \frac{\sqrt[3]{27^2}}{\sqrt[3]{8^2}}$

Step 8: Simplify the roots

$\sqrt[3]{27^2} = (27^2)^{\frac{1}{3}}$

$\sqrt[3]{8^2} = (8^2)^{\frac{1}{3}}$

Step 9: Simplify the powers of powers

$(27^2)^{\frac{1}{3}} = 27^{\frac{2}{3}}$

$(8^2)^{\frac{1}{3}} = 8^{\frac{2}{3}}$

Step 10: Simplify the expression

$\frac{\sqrt[3]{27^2}}{\sqrt[3]{8^2}} = \frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}}$

Conclusion

In this article, we've simplified the expression $\left(\frac{8}{27}\right)^{-\frac{2}{3}}$ by following the steps outlined above. We've used the rule for negative exponents, rational exponents, fractional exponents, roots, powers of powers, and canceling out powers to simplify the expression. The final simplified expression is $\frac{27^{\frac{2}{3}}}{8^{\frac{2}{3}}}$ .