Problem 10 - Algebra 2 and Trigonometry

Question

In \(3-37,\) express each power as a rational number in simplest form. $$ (3 \times 12)^{\frac{1}{2}} $$

Step-by-Step Solution

Answer

The expression simplifies to 6.

Step 1: Calculate the Product

First, calculate the product of the numbers inside the parentheses. Multiply 3 and 12 together: \[ 3 \times 12 = 36 \]

Step 2: Apply the Exponent

Next, apply the exponent \( \frac{1}{2} \), which is equivalent to finding the square root of the resulting product. Consider the expression \( 36^{\frac{1}{2}} \), which means \( \sqrt{36} \).The square root of 36 is:\[ \sqrt{36} = 6 \]

Step 3: Express as a Rational Number

The result from the previous step, \(6\), is a rational number (and also an integer). Therefore, the expression simplified in its simplest rational form is \(6\).

Key Concepts

Rational Numbers

A rational number is any number that can be expressed as the quotient or fraction \( \frac{p}{q} \), where \( p \) and \( q \) are integers and \( q eq 0 \). In simple terms, rational numbers include all fractions, such as \( \frac{1}{2} \) or \( \frac{3}{4} \), as well as whole numbers like 4 or -7 because they can be written as \( \frac{4}{1} \) or \( \frac{-7}{1} \). These numbers are "rational" because they ultimately stem from a ratio of two integers.
Understanding the nature of rational numbers is crucial in simplifying expressions like \((3 \times 12)^{\frac{1}{2}}\). When we calculated \(36^{\frac{1}{2}} = 6\), the result, 6, is a rational number because it can be seen as \( \frac{6}{1} \).

• Rational numbers can be positive, negative, or zero.
• They can be expressed in decimal form (either terminating, such as 0.25, or repeating, such as 0.333...).
• Every integer is a rational number, as it can be expressed with a denominator of 1.

Exploring how rational numbers integrate into mathematical expressions helps in understanding how to simplify complex computations.

Square Roots

A square root asks us to find a particular number that, when multiplied by itself, results in the original number. The square root of a number \( x \) is written as \( \sqrt{x} \). The operation is used to revert a number back from being squared. For example, \( \sqrt{36} = 6 \) because \( 6 \times 6 = 36 \).
In the expression \((3 \times 12)^{\frac{1}{2}}\), the exponent \( \frac{1}{2} \) signals the operation to find the square root. This means you are looking for a number that, when squared, returns to the product inside the parentheses. By breaking down the expression, \( (3 \times 12) = 36 \), and then finding \( 36^{\frac{1}{2}} = \sqrt{36} = 6 \), we simplify the expression to its fundamental value.

• The square root operation only applies to non-negative numbers in the context of real numbers.
• In mathematics, each positive number has two square roots: a positive and a negative one (e.g., \( x \) and \( -x \)), but by convention, we refer to the principal (positive) square root.
• Square roots can also be estimated in cases where they don't result in an exact integer, representing irrational numbers like \( \sqrt{2} \).

Grasping square roots allows students to simplify expressions involving powers of \( \frac{1}{2} \), forming a base for further understanding of algebraic structures.

Exponents

Exponents are a powerful mathematical tool allowing for the expression of repeated multiplication. An exponent of \( n \) on a base number \( x \), written as \( x^n \), means \( x \) is multiplied by itself \( n \) times. Exponents can also be fractions, like \( \frac{1}{2} \), which denote roots rather than repeated multiplication.
In our given problem, \((3 \times 12)^{\frac{1}{2}}\), the exponent \( \frac{1}{2} \) signifies taking the square root of the expression, simplifying it in a compact way. By using exponents, we compactly write complex operations that streamline calculations and expressions in mathematics.

• A fractional exponent like \( \frac{1}{n} \) corresponds to taking the nth root of the base number.
• Exponents help condense lengthy multiplication into a manageable form.
• Negative exponents indicate reciprocals. For example, \( x^{-n} = \frac{1}{x^n} \).

Understanding exponents, and how they translate into roots or powers, equips learners with a vital tool for tackling advanced mathematical problems efficiently.