Discover the answers you need at Westonci.ca, a dynamic Q&A platform where knowledge is shared freely by a community of experts. Our platform offers a seamless experience for finding reliable answers from a network of experienced professionals. Connect with a community of professionals ready to provide precise solutions to your questions quickly and accurately.

Simplify by rationalizing the denominator:

(a) [tex]\frac{1+\sqrt{7}}{1-\sqrt{7}}[/tex]

(b) [tex]\frac{1}{\sqrt{6}-\sqrt{5}}[/tex]

(c) [tex]\frac{1}{2\sqrt{5}-\sqrt{3}}[/tex]

(d) [tex]\frac{5+2\sqrt{3}}{7+4\sqrt{3}}[/tex]

(e) [tex]\frac{4\sqrt{3}+5\sqrt{2}}{\sqrt{48}+\sqrt{18}}[/tex]


Sagot :

### Simplifying by Rationalizing the Denominator

(a) [tex]\(\frac{1+\sqrt{7}}{1-\sqrt{7}}\)[/tex]

To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator, [tex]\(1 + \sqrt{7}\)[/tex]:

[tex]\[ \frac{(1 + \sqrt{7})(1 + \sqrt{7})}{(1 - \sqrt{7})(1 + \sqrt{7})} \][/tex]

Expanding both the numerator and the denominator:

Numerator:
[tex]\[ (1 + \sqrt{7})(1 + \sqrt{7}) = 1 + 2\sqrt{7} + 7 = 8 + 2\sqrt{7} \][/tex]

Denominator:
[tex]\[ (1 - \sqrt{7})(1 + \sqrt{7}) = 1 - 7 = -6 \][/tex]

Thus:

[tex]\[ \frac{8 + 2\sqrt{7}}{-6} = -\frac{8}{6} - \frac{2\sqrt{7}}{6} = -\frac{4}{3} - \frac{\sqrt{7}}{3} \][/tex]

The simplified result is approximately [tex]\(-2.21525043702153\)[/tex].

---

(b) [tex]\(\frac{1}{\sqrt{6}-\sqrt{5}}\)[/tex]

To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator, [tex]\(\sqrt{6} + \sqrt{5}\)[/tex]:

[tex]\[ \frac{1 \cdot (\sqrt{6} + \sqrt{5})}{(\sqrt{6} - \sqrt{5})(\sqrt{6} + \sqrt{5})} \][/tex]

Expanding both the numerator and the denominator:

Numerator:
[tex]\[ \sqrt{6} + \sqrt{5} \][/tex]

Denominator:
[tex]\[ (\sqrt{6} - \sqrt{5})(\sqrt{6} + \sqrt{5}) = 6 - 5 = 1 \][/tex]

Thus:

[tex]\[ \sqrt{6} + \sqrt{5} \][/tex]

The simplified result is approximately [tex]\(4.685557720282975\)[/tex].

---

(c) [tex]\(\frac{1}{2 \sqrt{5}-\sqrt{3}}\)[/tex]

To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator, [tex]\(2 \sqrt{5} + \sqrt{3}\)[/tex]:

[tex]\[ \frac{1 \cdot (2 \sqrt{5} + \sqrt{3})}{(2 \sqrt{5} - \sqrt{3})(2 \sqrt{5} + \sqrt{3})} \][/tex]

Expanding both the numerator and the denominator:

Numerator:
[tex]\[ 2 \sqrt{5} + \sqrt{3} \][/tex]

Denominator:
[tex]\[ (2 \sqrt{5})^2 - (\sqrt{3})^2 = 20 - 3 = 17 \][/tex]

Thus:

[tex]\[ \frac{2 \sqrt{5} + \sqrt{3}}{17} \][/tex]

The simplified result is approximately [tex]\(0.36495216250402684\)[/tex].

---

(d) [tex]\(\frac{5+2 \sqrt{3}}{7+4 \sqrt{3}}\)[/tex]

To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator, [tex]\(7 - 4 \sqrt{3}\)[/tex]:

[tex]\[ \frac{(5+2 \sqrt{3})(7 - 4 \sqrt{3})}{(7+4 \sqrt{3})(7-4 \sqrt{3})} \][/tex]

Expanding both the numerator and the denominator:

Numerator:
[tex]\[ (5+2 \sqrt{3})(7 - 4 \sqrt{3}) = 35 - 20 \sqrt{3} + 14 \sqrt{3} - 24 = 11 - 6 \sqrt{3} \][/tex]

Denominator:
[tex]\[ (7+4 \sqrt{3})(7-4 \sqrt{3}) = 49 - (4 \sqrt{3})^2 = 49 - 48 = 1 \][/tex]

Thus:

[tex]\[ 11 - 6 \sqrt{3} \][/tex]

The simplified result is approximately [tex]\(0.6076951545867362\)[/tex].

---

(e) [tex]\(\frac{4 \sqrt{3}+5 \sqrt{2}}{\sqrt{48}+\sqrt{18}}\)[/tex]

First simplify the denominator:

[tex]\[ \sqrt{48} = 4 \sqrt{3}, \quad \sqrt{18} = 3 \sqrt{2} \][/tex]

Thus the expression becomes:

[tex]\[ \frac{4 \sqrt{3} + 5 \sqrt{2}}{4 \sqrt{3} + 3 \sqrt{2}} \][/tex]

To rationalize the denominator, we multiply the numerator and the denominator by the conjugate of the denominator, [tex]\(4 \sqrt{3} - 3 \sqrt{2}\)[/tex]:

[tex]\[ \frac{(4 \sqrt{3} + 5 \sqrt{2})(4 \sqrt{3} - 3 \sqrt{2})}{(4 \sqrt{3} + 3 \sqrt{2})(4 \sqrt{3} - 3 \sqrt{2})} \][/tex]

Expanding both the numerator and the denominator:

Numerator:
[tex]\[ (4 \sqrt{3} + 5 \sqrt{2})(4 \sqrt{3} - 3 \sqrt{2}) = 48 - 15 \sqrt{6} \][/tex]

Denominator:
[tex]\[ (4 \sqrt{3})^2 - (3 \sqrt{2})^2 = 48 - 18 = 30 \][/tex]

Thus:

[tex]\[ \frac{48 - 15 \sqrt{6}}{30} = \frac{48}{30} - \frac{15 \sqrt{6}}{30} = \frac{8}{5} - \frac{\sqrt{6}}{2} \][/tex]

The simplified result is approximately [tex]\(1.2531972647421807\)[/tex].
Thanks for stopping by. We strive to provide the best answers for all your questions. See you again soon. Thanks for using our service. We're always here to provide accurate and up-to-date answers to all your queries. Find reliable answers at Westonci.ca. Visit us again for the latest updates and expert advice.