Problem

Simplify ( fourth root of 4)( cube root of 4)

The question is asking to perform simplification on the product of two different roots of the number 4. Specifically, it asks to multiply the fourth root of 4 by the cube root of 4 and then express the result in its simplest form. The fourth root of a number is a value that when raised to the power of four gives back that original number, and the cube root of a number is a value that when raised to the power of three returns that original number. This operation likely involves using the properties of exponents and radicals to simplify the expression.

$\left(\right. \sqrt[4]{4} \left.\right) \left(\right. \sqrt[3]{4} \left.\right)$

Answer

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Solution:

Step 1:

Express the number 4 as $2^2$. Thus, the expression becomes $\sqrt[4]{2^2} \cdot \sqrt[3]{4}$.

Step 2:

Transform $\sqrt[4]{2^2}$ into $\sqrt{\sqrt{2^2}}$. The expression now reads $\sqrt{\sqrt{2^2}} \cdot \sqrt[3]{4}$.

Step 3:

Extract terms from under the radical sign, assuming all numbers are positive real numbers. The expression simplifies to $\sqrt{2} \cdot \sqrt[3]{4}$.

Step 4:

Proceed to multiply $\sqrt{2} \cdot \sqrt[3]{4}$.

Step 4.1:

Convert the expression to have a common index of 6.

Step 4.1.1:

Using the rule $\sqrt[n]{a^x} = a^{\frac{x}{n}}$, rewrite $\sqrt{2}$ as $2^{\frac{1}{2}}$. The expression is now $2^{\frac{1}{2}} \cdot \sqrt[3]{4}$.

Step 4.1.2:

Express $2^{\frac{1}{2}}$ as $2^{\frac{3}{6}}$. The expression updates to $2^{\frac{3}{6}} \cdot \sqrt[3]{4}$.

Step 4.1.3:

Rewrite $2^{\frac{3}{6}}$ as $\sqrt[6]{2^3}$. The expression becomes $\sqrt[6]{2^3} \cdot \sqrt[3]{4}$.

Step 4.1.4:

Use the rule $\sqrt[n]{a^x} = a^{\frac{x}{n}}$ to convert $\sqrt[3]{4}$ into $4^{\frac{1}{3}}$. The expression is now $\sqrt[6]{2^3} \cdot 4^{\frac{1}{3}}$.

Step 4.1.5:

Change $4^{\frac{1}{3}}$ to $4^{\frac{2}{6}}$. The expression updates to $\sqrt[6]{2^3} \cdot 4^{\frac{2}{6}}$.

Step 4.1.6:

Rewrite $4^{\frac{2}{6}}$ as $\sqrt[6]{4^2}$. The expression is now $\sqrt[6]{2^3} \cdot \sqrt[6]{4^2}$.

Step 4.2:

Combine the terms using the product rule for radicals to get $\sqrt[6]{2^3 \cdot 4^2}$.

Step 4.3:

Represent the number 4 as $2^2$. The expression becomes $\sqrt[6]{2^3 \cdot (2^2)^2}$.

Step 4.4:

Apply the power rule to the exponents in $(2^2)^2$.

Step 4.4.1:

Using the power rule $(a^m)^n = a^{mn}$, the expression simplifies to $\sqrt[6]{2^3 \cdot 2^{2 \cdot 2}}$.

Step 4.4.2:

Multiply 2 by 2 to get $\sqrt[6]{2^3 \cdot 2^4}$.

Step 4.5:

Combine the exponents using the power rule $a^m \cdot a^n = a^{m+n}$, resulting in $\sqrt[6]{2^{3+4}}$.

Step 4.6:

Add the exponents 3 and 4 to obtain $\sqrt[6]{2^7}$.

Step 5:

Raise 2 to the power of 7 to get $\sqrt[6]{128}$.

Step 6:

Decompose 128 into $2^6 \cdot 2$.

Step 6.1:

Factor out 64 from 128, leading to $\sqrt[6]{64 \cdot 2}$.

Step 6.2:

Express 64 as $2^6$, resulting in $\sqrt[6]{2^6 \cdot 2}$.

Step 7:

Extract terms from under the radical to get $2 \cdot \sqrt[6]{2}$.

Step 8:

Present the result in various forms:

  • Exact Form: $2 \cdot \sqrt[6]{2}$
  • Decimal Form: Approximately $2.24492409 \ldots$

Knowledge Notes:

  • Radicals and Exponents: The radical expression $\sqrt[n]{a}$ is equivalent to $a^{\frac{1}{n}}$. When dealing with radicals, it's often useful to express numbers in their prime factorized form to simplify the radical.

  • Simplifying Radicals: To simplify a radical, one can pull out squares, cubes, etc., from under the radical sign. If the index of the radical and the exponent have a common multiple, it is possible to rewrite them with a common index to further simplify.

  • Product Rule for Radicals: $\sqrt[n]{a} \cdot \sqrt[n]{b} = \sqrt[n]{a \cdot b}$ allows us to combine radicals with the same index.

  • Power Rule: $(a^m)^n = a^{mn}$ is used to simplify expressions where an exponent is raised to another exponent.

  • Combining Exponents: When multiplying like bases, add the exponents: $a^m \cdot a^n = a^{m+n}$.

  • Exact vs. Decimal Form: The exact form of a number is the simplified radical form, while the decimal form is an approximate value obtained by calculating the radical expression to a certain number of decimal places.

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