Negative Exponents Practice Problems - Master Powers with Negative Exponents

Master negative exponents with step-by-step practice problems. Learn to convert negative powers to fractions, simplify expressions, and solve complex algebraic equations.

πŸ“šMaster Negative Exponents Through Interactive Practice
  • Convert expressions with negative exponents to positive fraction form using a^(-n) = 1/a^n
  • Simplify complex fractions containing bases with negative exponents
  • Apply negative exponent rules to algebraic expressions with variables and coefficients
  • Solve multi-step problems involving division of powers with negative exponents
  • Master fraction inversion when entire fractions have negative exponents
  • Combine negative exponent rules with other power laws for complex expressions

Understanding Negative Exponents

Complete explanation with examples

When we see any number(positive or negative) raised to a negative power we can convert the expression into a fraction and we will do it as follows:
the numerator will be 11, the denominator will be the base of the power as seen in the original exercise, but now, with a positive exponent.
That is to say, in the denominator we will invert the exponent to positive.
Pay attention, we will not modify the sign of the base of the potentiation even if it is negative.
Property formula:
aβˆ’n=1ana^{-n}=\frac {1}{a^n}
This property also applies to algebraic expressions.

Detailed explanation

Practice Negative Exponents

Test your knowledge with 18 quizzes

\( \frac{1}{8^3}=\text{?} \)

Examples with solutions for Negative Exponents

Step-by-step solutions included
Exercise #1

Insert the corresponding expression:

1202= \frac{1}{20^2}=

Step-by-Step Solution

To solve this problem, we will use the properties of exponents. Specifically, we will convert the expression 1202 \frac{1}{20^2} into a form that uses a negative exponent. The general relationship is that 1an=aβˆ’n \frac{1}{a^n} = a^{-n} .

Applying this rule to the given expression:

  • Step 1: Identify the current form, which is 1202 \frac{1}{20^2} .
  • Step 2: Apply the negative exponent rule: 1202=20βˆ’2 \frac{1}{20^2} = 20^{-2} .
  • Step 3: This expression, 20βˆ’2 20^{-2} , represents 1202 \frac{1}{20^2} using a negative exponent.

Therefore, the expression 1202 \frac{1}{20^2} can be expressed as 20βˆ’2 20^{-2} , which aligns with choice 1.

Answer:

20βˆ’2 20^{-2}

Video Solution
Exercise #2

Insert the corresponding expression:

167= \frac{1}{6^7}=

Step-by-Step Solution

To solve this problem, we will rewrite the expression 167\frac{1}{6^7} using the rules of exponents:

Step 1: Identify the given fraction.

We start with 167\frac{1}{6^7}, where the base in the denominator is 6, and the exponent is 7.

Step 2: Apply the formula for negative exponents.

The formula aβˆ’n=1ana^{-n} = \frac{1}{a^n} allows us to rewrite a reciprocal power as a negative exponent. This means the expression 167\frac{1}{6^7} can be rewritten as 6βˆ’76^{-7}.

Step 3: Conclude with the answer.

By transforming 167\frac{1}{6^7} to its equivalent form using negative exponents, the expression becomes 6βˆ’76^{-7}.

Therefore, the correct expression is 6βˆ’7\boxed{6^{-7}}, which corresponds to choice 2 in the given options.

Answer:

6βˆ’7 6^{-7}

Video Solution
Exercise #3

Insert the corresponding expression:

(13)βˆ’4= \left(\frac{1}{3}\right)^{-4}=

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the given expression with a negative exponent.
  • Step 2: Apply the rule for negative exponents, which allows us to convert the expression into a positive exponent form.
  • Step 3: Perform the calculation of the new expression.

Now, let's work through each step:

Step 1: The expression given is (13)βˆ’4 \left(\frac{1}{3}\right)^{-4} , which involves a negative exponent.

Step 2: According to the exponent rule (ab)βˆ’n=(ba)n \left(\frac{a}{b}\right)^{-n} = \left(\frac{b}{a}\right)^n , we can rewrite the expression with a positive exponent by inverting the fraction:

(13)βˆ’4=(31)4=34 \left(\frac{1}{3}\right)^{-4} = \left(\frac{3}{1}\right)^4 = 3^4 .

Step 3: Calculate 34 3^4 .

The calculation 34 3^4 is as follows:

34=3Γ—3Γ—3Γ—3=81 3^4 = 3 \times 3 \times 3 \times 3 = 81 .

However, since the problem specifically asks for the corresponding expression before calculation to numerical form, the answer remains 34 3^4 .

Therefore, the answer to the problem, in terms of an equivalent expression, is 34 3^4 .

Answer:

34 3^4

Video Solution
Exercise #4

Insert the corresponding expression:

132= \frac{1}{3^2}=

Step-by-Step Solution

To solve this problem, we'll use the rule of negative exponents:

  • Step 1: Identify that the given expression is 132\frac{1}{3^2}.
  • Step 2: Recognize that 132\frac{1}{3^2} can be rewritten using the negative exponent rule.
  • Step 3: Apply the formula 1an=aβˆ’n\frac{1}{a^n} = a^{-n} to the expression 132\frac{1}{3^2}.

Now, let's work through these steps:

Step 1: We have 132\frac{1}{3^2} where 3 is the base and 2 is the exponent.

Step 2: Using the formula, convert the denominator 323^2 to 3βˆ’23^{-2}.

Step 3: Thus, 132=3βˆ’2\frac{1}{3^2} = 3^{-2}.

Therefore, the solution to the problem is 3βˆ’23^{-2}.

Answer:

3βˆ’2 3^{-2}

Video Solution
Exercise #5

Insert the corresponding expression:

142= \frac{1}{4^2}=

Step-by-Step Solution

To solve the problem of expressing 142\frac{1}{4^2} using powers with negative exponents:

  • Identify the base in the denominator: 4 raised to the power 2.
  • Apply the rule for negative exponents that states 1an=aβˆ’n\frac{1}{a^n} = a^{-n}.
  • Express 142\frac{1}{4^2} as 4βˆ’24^{-2}.

Thus, the expression 142\frac{1}{4^2} can be rewritten as 4βˆ’2 4^{-2} .

Answer:

4βˆ’2 4^{-2}

Video Solution

Frequently Asked Questions

What is the rule for negative exponents?

+
The negative exponent rule states that a^(-n) = 1/a^n. When you see a negative exponent, you can rewrite it as a fraction with 1 in the numerator and the base with a positive exponent in the denominator.

How do you solve problems with negative exponents step by step?

+
Follow these steps: 1) Identify terms with negative exponents, 2) Apply the rule a^(-n) = 1/a^n to convert to fractions, 3) Simplify the resulting fractions, 4) Combine like terms if applicable. Always keep the base unchanged, only flip the exponent sign.

Does a negative exponent make the answer negative?

+
No, a negative exponent does not make the final answer negative. For example, 3^(-1) = 1/3, which is positive. The negative sign only affects the exponent's position, converting the expression to a fraction form.

How do you handle fractions with negative exponents?

+
When an entire fraction has a negative exponent like (a/b)^(-n), you invert the fraction and make the exponent positive: (a/b)^(-n) = (b/a)^n. The numerator and denominator switch places.

What are common mistakes when working with negative exponents?

+
Common errors include: β€’ Thinking negative exponents create negative results β€’ Changing the sign of the base instead of just the exponent β€’ Forgetting to apply the rule to each term separately β€’ Not simplifying fractions after conversion

How do negative exponents work with variables and coefficients?

+
Separate the coefficient from the variable first. For example, 3Β·5x^(-7) = 3Β·5Β·x^(-7) = 3Β·5Β·(1/x^7) = 15/x^7. Only the variable with the negative exponent gets converted to fraction form.

Can you use negative exponent rules with algebraic expressions?

+
Yes, negative exponent rules apply to all algebraic expressions. Whether you have numbers, variables, or complex expressions as the base, the rule a^(-n) = 1/a^n always applies consistently.

What's the difference between (-3)^(-2) and -3^(-2)?

+
(-3)^(-2) means the entire negative number is raised to the power: (-3)^(-2) = 1/(-3)^2 = 1/9. However, -3^(-2) means only 3 has the negative exponent: -3^(-2) = -(1/3^2) = -1/9.

More Negative Exponents Questions

Continue Your Math Journey

Practice by Question Type