Question

multiply 6 root 5 by 2 root 5

Answer 1

$6\sqrt{5}\times 2\sqrt{5}=60$

Concept :

If $a$ be a number, then we have the relation

$\quad\sqrt{a^{2}}=a$,

which is obtained from

$\sqrt{a^{2}}=(a^{2})^{\frac{1}{2}}=a^{\frac{2}{2}}=a^{1}=a$.

Step-by-step explanation :

Now, $6\sqrt{5}\times 2\sqrt{5}$

• Tip. Group the rational numbers together and the irrational number together. Then find their products.

$=(6\times 2)\times (\sqrt{5}\times\sqrt{5})$

$=12\times \sqrt{5\times 5}$

$=12\times \sqrt{5^{2}}$

$=12\times 5$

$=60$

Thus, $6\sqrt{5}\times 2\sqrt{5}=60$.