Problem 63

Question

Simplify each radical expression. \(n\) is an even number. $$ \sqrt[n]{m^{2 n}} $$

Step-by-Step Solution

Verified
Answer
The simplified form of the given radical expression is \(m^2\).
1Step 1: Identify Terms
Identify the terms in the radical expression. Here, \(n\) is the root of the radical, and \(m^{2n}\) is the radicand.
2Step 2: Apply Rules of Indices and Simplify
Knowing that \(\sqrt[n]{m^{k n}} = m^k\) when \(n\) is even, we can simplify \(\sqrt[n]{m^{2n}}\) to \( m^2\).

Key Concepts

Simplifying RadicalsRules of IndicesEven Roots
Simplifying Radicals
Simplifying radicals is like unwrapping a gift to see what's inside. In mathematics, radicals are numbers or expressions with a root, like square roots or cube roots. Understanding how to simplify them makes solving equations much simpler.

To simplify a radical expression, the goal is to make it as "simple" as possible. This means expressing the root in its most reduced form. Let's start with a simple example:
  • The square root of 25 is simplified to 5. This is because 5 multiplied by itself (5 × 5) equals 25.
For more complex expressions, like the one in the exercise, we identify patterns and structures. The process involves recognizing factors that are powers of the index of the root. Take \(\sqrt[n]{m^{2n}}\), for instance. Here, we can see that the exponent \(2n\) is a multiple of \(n\).

This is key to simplification: dividing the exponent of the term inside the root by the value of \(n\). This way, \(m^{2n}\) becomes \(m^2\), as simplifying radicals allows us to "remove" the root and bring out a more straightforward expression.
Rules of Indices
The rules of indices help manage powers and roots efficiently. They act as a toolset for simplifying exponential expressions. In the context of simplification, when you see terms like \(m^{2n}\) inside a radical, rules of indices allow you to break down the powers into more manageable parts.
Here are some handy rules:
  • Product Law: This states that multiplying two exponents with the same base adds their powers: \(a^m \times a^n = a^{m+n}\).
  • Quotient Law: This handles division by subtracting the exponents: \(\frac{a^m}{a^n} = a^{m-n}\).
  • Power of a Power: This rule raises an exponent to another power: \((a^m)^n = a^{mn}\).
In this case, applying the rule for roots, if we have \(\sqrt[n]{m^{kn}}\), it simplifies directly to \(m^k\) when \(n\) is even. This works because the indices rule links the powers directly to roots.

Instead of performing complex calculations, we rely on these rules to leapfrog to the solution simply and efficiently, making our work with radicals smoother and faster.
Even Roots
Even roots, like square roots and fourth roots, hold a special position in the world of mathematics. They yield non-negative results (assuming we're dealing only with real numbers). This is because squaring or raising a number to an even power neutralizes negatives.
For the expression \(\sqrt[n]{m^{2n}}\) with \(n\) as an even number, we're effectively asking what number, when raised to the \(n\)-th power, results in our original term inside the root.
  • If \(n\) is 2 (a square root), \(m^{2n} = m^4\), simplifies to \(m^2\).
  • Even higher even roots (like fourth or sixth roots) follow the same logic but with higher exponents.
When working with even roots, you need not worry about negative results magically appearing. Instead, focus on leveraging the even power to simplify the expression outright.

By making sense of even roots, we're able to unravel complex terms into simplified forms that remove uncertainty and highlight the core components.