Problem

Simplify 3/(3-2 square root of 3)

The question is asking for the simplification of a given mathematical expression. Specifically, the expression is a rational expression (a fraction), where the numerator is the integer 3, and the denominator is the result of subtracting 2 times the square root of 3 from the integer 3. The goal is to manipulate the expression using algebraic techniques to reach a simpler or more standard form, typically one that no longer has a radical (square root) in the denominator.

$\frac{3}{3 - 2 \sqrt{3}}$

Answer

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Solution:

Step:1

Rationalize the denominator of $\frac{3}{3 - 2\sqrt{3}}$ by multiplying by the conjugate $\frac{3 + 2\sqrt{3}}{3 + 2\sqrt{3}}$.

$$\frac{3}{3 - 2\sqrt{3}} \cdot \frac{3 + 2\sqrt{3}}{3 + 2\sqrt{3}}$$

Step:2

Apply the multiplication to the numerators.

$$\frac{3 \cdot (3 + 2\sqrt{3})}{(3 - 2\sqrt{3}) \cdot (3 + 2\sqrt{3})}$$

Step:3

Use the difference of squares to expand the denominator.

$$\frac{3 \cdot (3 + 2\sqrt{3})}{9 - (2\sqrt{3})^2}$$

Step:4

Simplify the denominator.

$$\frac{3 \cdot (3 + 2\sqrt{3})}{9 - 12}$$

Step:5

Further simplify the expression.

Step:5.1

Isolate the negative sign from the denominator.

$$-1 \cdot (3 + 2\sqrt{3})$$

Step:5.2

Express the multiplication by the negative sign.

$$-(3 + 2\sqrt{3})$$

Step:6

Distribute the negative sign.

$$-3 - 2\sqrt{3}$$

Step:7

Final multiplication.

Step:7.1

Multiply $-1$ by $3$.

$$-3 - 2\sqrt{3}$$

Step:7.2

Multiply $2$ by $\sqrt{3}$ and apply the negative sign.

$$-3 - 2\sqrt{3}$$

Step:8

Present the final result in various forms.

Exact Form: $-3 - 2\sqrt{3}$ Decimal Form: Approximately $-6.46410161$

Knowledge Notes:

  1. Rationalizing the Denominator: This process involves multiplying the numerator and the denominator by the conjugate of the denominator to eliminate the square root from the denominator. The conjugate of a binomial $a + b$ is $a - b$.

  2. Difference of Squares: This is a pattern used in algebra where $(a + b)(a - b) = a^2 - b^2$. It is used to simplify expressions where two terms are being multiplied by their conjugates.

  3. Distributive Property: This property states that $a(b + c) = ab + ac$. It is used to multiply a single term by each term inside a parenthesis.

  4. Conjugate: The conjugate of a binomial is obtained by changing the sign between two terms. For example, the conjugate of $3 - 2\sqrt{3}$ is $3 + 2\sqrt{3}$.

  5. Simplifying Expressions: This involves combining like terms and reducing expressions to their simplest form.

  6. Negative Sign Distribution: When distributing a negative sign through a parenthesis, it changes the sign of each term inside the parenthesis.

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