Problem

Simplify square root of 18x^11y^7

This problem is asking for the simplification of a radical expression. The expression includes a square root of a product that comprises a numerical term (18) and two algebraic terms with exponents (x^11 and y^7). Simplifying this expression involves factoring out square numbers from within the square root to outside the square root and reducing the exponents of the variables according to the rules for square roots of powers.

$\sqrt{18 x^{11} y^{7}}$

Answer

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Solution:

Step 1: Decompose the expression into perfect squares and remaining factors

Rewrite the expression $18x^{11}y^{7}$ as $(3x^{5}y^{3})^{2} \cdot 2xy$.

Step 1.1: Extract the square factor from 18

Factor 9 from 18 as $\sqrt{9 \cdot 2x^{11}y^{7}}$.

Step 1.2: Express 9 as a square of 3

Represent 9 as $3^{2}$, yielding $\sqrt{3^{2} \cdot 2x^{11}y^{7}}$.

Step 1.3: Separate the even power of x

Extract $x^{10}$ from $x^{11}$ as $\sqrt{3^{2} \cdot 2(x^{10}x)y^{7}}$.

Step 1.4: Rewrite $x^{10}$ as a square

Express $x^{10}$ as $(x^{5})^{2}$, resulting in $\sqrt{3^{2} \cdot 2((x^{5})^{2}x)y^{7}}$.

Step 1.5: Separate the even power of y

Factor $y^{6}$ from $y^{7}$ as $\sqrt{3^{2} \cdot 2((x^{5})^{2}x)(y^{6}y)}$.

Step 1.6: Rewrite $y^{6}$ as a square

Rewrite $y^{6}$ as $(y^{3})^{2}$, giving $\sqrt{3^{2} \cdot 2((x^{5})^{2}x)((y^{3})^{2}y)}$.

Step 1.7: Rearrange the x term

Rearrange to place the x term outside the perfect square as $\sqrt{3^{2} \cdot 2((x^{5})^{2})(y^{3})^{2}xy}$.

Step 1.8: Rearrange the 2 factor

Rearrange to place the 2 factor outside the perfect square as $\sqrt{(3^{2}((x^{5})^{2})(y^{3})^{2}) \cdot 2xy}$.

Step 1.9: Combine the perfect squares

Combine the perfect squares into a single term as $\sqrt{(3x^{5}y^{3})^{2} \cdot 2xy}$.

Step 1.10: Add parentheses around the non-square factors

Introduce parentheses to clearly separate the non-square factors as $\sqrt{(3x^{5}y^{3})^{2} \cdot (2xy)}$.

Step 1.11: Ensure the expression is properly parenthesized

Verify that the expression is correctly parenthesized as $\sqrt{(3x^{5}y^{3})^{2} \cdot (2xy)}$.

Step 2: Simplify the radical expression

Extract the perfect square terms from under the radical to obtain $3x^{5}y^{3}\sqrt{2xy}$.

Knowledge Notes:

To simplify a square root involving variables and coefficients, we follow these steps:

  1. Factor the coefficient into a product of perfect squares and other factors.

  2. Rewrite each variable with an even exponent as the square of a variable with half that exponent.

  3. Separate the perfect squares from the non-square terms.

  4. Extract the square root of the perfect squares, which can be done without a radical since they are perfect squares.

  5. Leave the non-square terms under the radical.

In this problem, we are given the expression $\sqrt{18x^{11}y^{7}}$. We need to simplify it by finding perfect square factors and extracting them from under the radical. We use the properties of exponents and the fact that the square root of a perfect square is just the base of the exponent. We also use the associative property of multiplication to group terms under the radical in a way that reveals perfect squares. The final result is a simplified expression with some terms outside the radical (those that were perfect squares) and the remaining terms inside the radical.

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