Question

$$\frac{ 3 \sqrt{ { 7 }^{ 2 } \times 3 \sqrt{ 7 } } }{ \sqrt{ 7 } }$$

Answer

$$(21*7^(1/4)*sqrt(21))/7$$

Solution


Simplify  \({7}^{2}\)  to  \(49\).
\[\frac{3\sqrt{49\times 3\sqrt{7}}}{\sqrt{7}}\]
Simplify  \(49\times 3\sqrt{7}\)  to  \(147\sqrt{7}\).
\[\frac{3\sqrt{147\sqrt{7}}}{\sqrt{7}}\]
Use this rule: \(\sqrt{ab}=\sqrt{a}\sqrt{b}\).
\[\frac{3\sqrt{147}\sqrt{\sqrt{7}}}{\sqrt{7}}\]
Simplify  \(\sqrt{147}\)  to  \(7\sqrt{3}\).
\[\frac{3\times 7\sqrt{3}\sqrt{\sqrt{7}}}{\sqrt{7}}\]
Use this rule: \({({x}^{a})}^{b}={x}^{ab}\).
\[\frac{3\times 7\sqrt{3}\times {7}^{\frac{1\times 1}{2\times 2}}}{\sqrt{7}}\]
Simplify  \(1\times 1\)  to  \(1\).
\[\frac{3\times 7\sqrt{3}\sqrt[2\times 2]{7}}{\sqrt{7}}\]
Simplify  \(2\times 2\)  to  \(4\).
\[\frac{3\times 7\sqrt{3}\sqrt[4]{7}}{\sqrt{7}}\]
Simplify  \(3\times 7\sqrt{3}\sqrt[4]{7}\)  to  \(21\sqrt{3}\sqrt[4]{7}\).
\[\frac{21\sqrt{3}\sqrt[4]{7}}{\sqrt{7}}\]
Regroup terms.
\[\frac{21\sqrt[4]{7}\sqrt{3}}{\sqrt{7}}\]
Rationalize the denominator: \(\frac{21\sqrt[4]{7}\sqrt{3}}{\sqrt{7}} \cdot \frac{\sqrt{7}}{\sqrt{7}}=\frac{21\sqrt[4]{7}\sqrt{3}\sqrt{7}}{7}\).
\[\frac{21\sqrt[4]{7}\sqrt{3}\sqrt{7}}{7}\]
Simplify  \(21\sqrt[4]{7}\sqrt{3}\sqrt{7}\)  to  \(21\sqrt[4]{7}\sqrt{21}\).
\[\frac{21\sqrt[4]{7}\sqrt{21}}{7}\]
Simplify square root.
\[\frac{21\sqrt{21}\sqrt[4]{7}}{7}\]
Regroup terms.
\[\frac{21\sqrt[4]{7}\sqrt{21}}{7}\]

Decimal Form: 22.361731