Problem 33 - Algebra 1

Question

Evaluate the power. $$ 9^{3} $$

Step-by-Step Solution

Answer

The solution to \(9^{3}\) is 729.

Step 1: Understanding the exponent notation

The notation \(9^{3}\) means 9 is the base, and 3 is the exponent. This notation means multiplying the base by itself, the number of times equal to the exponent. In this case, it means multiplying 9 by itself 3 times.

Step 2: Calculating the power

Now do the multiplication. Calculate \(9 * 9 * 9\).

Key Concepts

Evaluating Powers

Understanding how to evaluate powers is fundamental in mathematics. 'Evaluating powers' simply means calculating the value of a number when it's raised to a certain exponent. An exponent is a small number placed to the upper right of a base number that tells you how many times to multiply the base by itself. For example, in the expression \( 9^3 \), the number 9 is the base and 3 is the exponent, indicating that 9 needs to be multiplied by itself a total of three times.

So, when we interpret \( 9^3 \), it can be rewritten as \( 9 \times 9 \times 9 \). Performing the multiplication, \( 9 \times 9 = 81 \) and then \( 81 \times 9 = 729 \). Thus, \( 9^3 \) evaluates to 729. This is a simple example, but evaluating powers becomes essential when dealing with more complex math where powers have higher exponents or when the base is not a whole number.

Exponent Notation

The 'exponent notation' is a way of expressing repeated multiplication succinctly. In this compact form, rather than writing out the same number multiplied by itself multiple times, we use two numbers: the base and the exponent.

The base is the number being multiplied, and the exponent, which is sometimes called the power, indicates how many times the base is used as a factor. The exponent is written as a superscript number. For instance, with the expression \( 9^3 \), we know that the base is 9 and the exponent is 3. It's important not to confuse exponents with coefficients or subscripts, which have different placements and meanings in mathematical notation. Exponent notation is particularly useful in scientific and engineering fields, as it allows for a more straightforward representation of very large or very small numbers.

Multiplication of Bases

When dealing with exponentiation, 'multiplication of bases' refers to the process of multiplying a number by itself a certain number of times as indicated by the exponent. In our previous example, the base 9 is multiplied by itself three times because of the exponent 3. This concept is extended when multiplying powers with the same base.

For example, if you have two expressions with the same base such as \( 9^2 \) and \( 9^3 \) and you want to multiply them together, you simply add the exponents to get \( 9^{2+3} = 9^5 \). This rule reflects the fact that you're multiplying the base a total of 2 + 3 times. It's crucial to note that this rule only applies when the bases are the same; when bases differ, this additive rule for exponents doesn't hold. Understanding the multiplication of bases is key for simplifying expressions and solving equations involving powers.