Question

Multiply $3\sqrt{28}\text{by}2\sqrt{7}$.

Answer 1

Step: Multiply
We are given two irrational numbers $3\sqrt{28}\text{and}2\sqrt{7}$.
We need to multiply these numbers.
So, $\left(3\sqrt{28}\right)\times \left(2\sqrt{7}\right)$
$=3\times 2\times \sqrt{7}\times \sqrt{28}$

We can write $\sqrt{28}$ as $\sqrt{7\times 4}$.
$=3\times 2\times \sqrt{7}\times \sqrt{7\times 4}$

$=6\times \sqrt{7}\times \sqrt{7}\times \sqrt{4}$

As we know that, $\sqrt{7}\times \sqrt{7}$ will be 7 and $\sqrt{4}$ will be 2.
$=6\times 7\times 2$

$=84$
Thus, the multiplication of the given numbers $3\sqrt{28}\text{and}2\sqrt{7}$ is 84 .