Exponent Calculator (Power Calculator)
Calculate the result of exponentiation, where a base number is raised to the power of an exponent. Enter the base (a) and the exponent (n) to compute $a^n$.
Calculate $a^n$
Understanding Exponents
Exponentiation is a fundamental mathematical operation, written as $\bf{a^n}$, involving two numbers: the base ($a$) and the exponent or power ($n$). When $n$ is a positive integer, exponentiation represents repeated multiplication of the base, $n$ times.
$a^n = \underbrace{a \times a \times \dots \times a}_{n \text{ times}}$
Exponents can also be zero, negative, or fractional (represented as decimals in this calculator), each with specific rules.
Basic Exponent Laws and Rules
$a^n \times a^m = a^{(n+m)}$
Multiply powers with the same base: add the exponents.
Ex: $2^2 \times 2^3 = 2^{(2+3)} = 2^5 = 32$
$\frac{a^m}{a^n} = a^{(m - n)}$
Divide powers with the same base: subtract the exponents.
Ex: $3^5 / 3^2 = 3^{(5-2)} = 3^3 = 27$
$(a^m)^n = a^{(m \times n)}$
Raise a power to another power: multiply the exponents.
Ex: $(4^2)^3 = 4^{(2 \times 3)} = 4^6 = 4096$
$(a \times b)^n = a^n \times b^n$
Raise a product to a power: distribute the exponent.
Ex: $(2 \times 3)^2 = 2^2 \times 3^2 = 4 \times 9 = 36$
$(\frac{a}{b})^n = \frac{a^n}{b^n}$ (where $b \neq 0$)
Raise a quotient to a power: distribute the exponent.
Ex: $(2/5)^2 = 2^2 / 5^2 = 4/25$
$a^{-n} = \frac{1}{a^n}$ (where $a \neq 0$)
Negative exponent means reciprocal of the base to the positive exponent.
Ex: $2^{-3} = 1 / 2^3 = 1/8$
$a^0 = 1$ (where $a \neq 0$)
Any non-zero base raised to the power of 0 equals 1.
Ex: $5^0 = 1$, $(-3)^0 = 1$
$a^1 = a$
Any base raised to the power of 1 is the base itself.
Ex: $7^1 = 7$
$a^{m/n} = \sqrt[n]{a^m} = (\sqrt[n]{a})^m$
Denominator is root, numerator is power. Input decimals (e.g., 0.5 for square root).
Ex: $8^{1/3} = \sqrt[3]{8} = 2$. $9^{3/2} = (\sqrt{9})^3 = 3^3 = 27$.
Calculator Capabilities and Limitations
- Accepts positive and negative bases.
- Accepts positive, negative, and zero exponents.
- Accepts decimal exponents (for fractional powers). Enter fractions like 1/2 as 0.5, 2/3 as 0.6666... etc.
- Does NOT compute imaginary numbers. If you enter a negative base with a non-integer exponent (e.g., $(-4)^{0.5}$), the result will be indicated as invalid or "NaN" (Not a Number), as this involves imaginary units ($i$).
Examples with Step-by-Step Solutions
Click on each example to see the calculation:
Example 1: Positive Integer Exponent ($5^3$)
Problem: Calculate $5^3$.
Steps:
- Identify the base ($a=5$) and the exponent ($n=3$).
- Since the exponent is a positive integer, multiply the base by itself 3 times.
- Calculation: $5 \times 5 \times 5 = 25 \times 5 = 125$.
Result: $5^3 = 125$.
Example 2: Negative Integer Exponent ($4^{-2}$)
Problem: Calculate $4^{-2}$.
Steps:
- Apply the Negative Exponent Rule: $a^{-n} = 1/a^n$.
- Here, $a=4$ and $n=2$. So, $4^{-2} = 1 / 4^2$.
- Calculate the denominator: $4^2 = 4 \times 4 = 16$.
- Calculation: $1 / 16$.
Result: $4^{-2} = 1/16 = 0.0625$.
Example 3: Zero Exponent ($(-7)^0$)
Problem: Calculate $(-7)^0$.
Steps:
- Apply the Zero Exponent Rule: $a^0 = 1$ (for any non-zero base $a$).
- The base is $a=-7$, which is non-zero.
Result: $(-7)^0 = 1$.
Example 4: Exponent of One ($10^1$)
Problem: Calculate $10^1$.
Steps:
- Apply the Exponent of One Rule: $a^1 = a$.
- The base is $a=10$.
Result: $10^1 = 10$.
Example 5: Decimal/Fractional Exponent ($9^{1.5}$)
Problem: Calculate $9^{1.5}$. (Note: 1.5 = 3/2)
Steps using Fractional Exponent Rule ($a^{m/n} = (\sqrt[n]{a})^m$):
- Identify $a=9$, $m=3$, $n=2$.
- Calculate the nth root: $\sqrt[2]{9} = \sqrt{9} = 3$.
- Raise the result to the mth power: $3^3 = 3 \times 3 \times 3 = 27$.
Steps using Decimal (Calculator Method):
- Enter Base = 9, Exponent = 1.5 into the calculator.
- The calculator computes $9^{1.5}$.
Result: $9^{1.5} = 27$.
Example 6: Negative Base, Even Exponent ($(-3)^4$)
Problem: Calculate $(-3)^4$.
Steps:
- Multiply the base $(-3)$ by itself 4 times.
- Calculation: $(-3) \times (-3) \times (-3) \times (-3)$
- $(9) \times (-3) \times (-3)$
- $(-27) \times (-3)$
- $81$ (Negative times negative is positive).
Result: $(-3)^4 = 81$. (Note: The result is positive because the exponent is even).
Example 7: Negative Base, Odd Exponent ($(-2)^3$)
Problem: Calculate $(-2)^3$.
Steps:
- Multiply the base $(-2)$ by itself 3 times.
- Calculation: $(-2) \times (-2) \times (-2)$
- $(4) \times (-2)$
- $-8$ (Positive times negative is negative).
Result: $(-2)^3 = -8$. (Note: The result is negative because the exponent is odd).
Example 8: Product Rule ($2^2 \times 2^3$)
Problem: Calculate $2^2 \times 2^3$.
Steps using Product Rule:
- The bases are the same (2). Add the exponents: $2 + 3 = 5$.
- Result is $2^5$.
- Calculate $2^5 = 2 \times 2 \times 2 \times 2 \times 2 = 32$.
Steps direct calculation:
- $2^2 = 4$.
- $2^3 = 8$.
- $4 \times 8 = 32$.
Result: $2^2 \times 2^3 = 32$.
Example 9: Quotient Rule ($10^6 / 10^4$)
Problem: Calculate $10^6 / 10^4$.
Steps using Quotient Rule:
- The bases are the same (10). Subtract the exponents: $6 - 4 = 2$.
- Result is $10^2$.
- Calculate $10^2 = 10 \times 10 = 100$.
Steps direct calculation:
- $10^6 = 1,000,000$.
- $10^4 = 10,000$.
- $1,000,000 / 10,000 = 100$.
Result: $10^6 / 10^4 = 100$.
Example 10: Power Rule ($(4^2)^3$)
Problem: Calculate $(4^2)^3$.
Steps using Power Rule:
- Multiply the exponents: $2 \times 3 = 6$.
- Result is $4^6$.
- Calculate $4^6 = 4 \times 4 \times 4 \times 4 \times 4 \times 4 = 4096$.
Steps direct calculation:
- Calculate inside the parenthesis: $4^2 = 16$.
- Calculate $16^3 = 16 \times 16 \times 16 = 256 \times 16 = 4096$.
Result: $(4^2)^3 = 4096$.
Frequently Asked Questions (FAQs)
What is the 'base' and 'exponent'?
In the expression $a^n$, '$a$' is the base (the number being multiplied) and '$n$' is the exponent (how many times the base is multiplied by itself, or other interpretations based on the rules).
How does this calculator handle $a^{-n}$?
It applies the rule $a^{-n} = 1/a^n$. For example, inputting Base=2, Exponent=-3 will calculate $1 / 2^3 = 1/8 = 0.0625$.
How do I enter fractional exponents like $8^{2/3}$?
You need to enter the exponent in its decimal form. For $2/3$, you would enter approximately 0.6666667 in the exponent field. For $1/2$, enter 0.5.
What happens with negative bases like $(-4)^{0.5}$?
Calculating a non-integer power (like 0.5, which is the square root) of a negative number results in an imaginary number (involving $i = \sqrt{-1}$). This calculator does not compute imaginary numbers and will display an error or "Invalid Input" message in such cases.
What result does the calculator give for $0^0$?
$0^0$ is mathematically indeterminate, meaning it doesn't have a single defined value. However, in many programming contexts and for certain mathematical conveniences (like in binomial expansions), it is often defined as 1. This calculator uses the standard JavaScript `Math.pow(0, 0)` function, which returns 1.
Where are exponents used?
Exponents are fundamental in many fields, including: science (scientific notation, exponential growth/decay), finance (compound interest calculations), computer science (data sizes, algorithms), statistics, engineering, and many other areas involving repeated multiplication or scaling relationships.