Respuesta :

Simplifying a fraction

We want to simplify the following expression:

[tex]\frac{2+\sqrt[]{3}}{2-\sqrt[]{3}}[/tex]

This means that we want to "remove" the denominator".

STEP 1

If we observe the denominator:

[tex](2-\sqrt[]{3})[/tex]

If we multiply it by

2 + √3, then

[tex]\begin{gathered} (2-\sqrt[]{3})(2+\sqrt[]{3}) \\ =4-\sqrt[]{3}^2=4-3=1 \end{gathered}[/tex]

STEP 2

We know that if we multiply both sides of a fraction by the same number or expression, the fraction will remain the same, then we multiply both sides by 2 + √3:

[tex]\frac{2+\sqrt[]{3}}{2-\sqrt[]{3}}=\frac{(2+\sqrt[]{3})(2+\sqrt[]{3})}{(2-\sqrt[]{3})(2+\sqrt[]{3})}[/tex]

For the denominator, as we analyzed before

[tex](2-\sqrt[]{3})(2+\sqrt[]{3})=1[/tex]

For the denominator:

[tex](2+\sqrt[]{3})(2+\sqrt[]{3})=(2+\sqrt[]{3})^2[/tex]

Then,

[tex]\frac{2+\sqrt[]{3}}{2-\sqrt[]{3}}=\frac{(2+\sqrt[]{3})(2+\sqrt[]{3})}{(2-\sqrt[]{3})(2+\sqrt[]{3})}=\frac{(2+\sqrt[]{3})^2}{1}=(2+\sqrt[]{3})^2[/tex]

STEP 3

Now, we can simplify the result:

[tex]\begin{gathered} (2+\sqrt[]{3})^2=(2+\sqrt[]{3})(2+\sqrt[]{3}) \\ =2^2+2\sqrt[]{3}+(\sqrt[]{3})^2+2\sqrt[]{3} \\ =4+4\sqrt[]{3}+3 \\ =7+4\sqrt[]{3} \end{gathered}[/tex]Answer: 7+4√3