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Multiplying Radical Expressions

In this video, we will multiply radical expressions.

Let’s start with simple expressions.
\sqrt{3}\times\sqrt{3}=\sqrt{9}=3
\sqrt{5}\times\sqrt{5}=\sqrt{25}=3

In other words,
\sqrt{7}\times\sqrt{7}=7
\sqrt{12}\times\sqrt{12}=12

Let’s try other examples:
\sqrt{5}\times\sqrt{7} would equal to \sqrt{35}
\sqrt{18}\times\sqrt{2} would equal to \sqrt{36}, which is a perfect square so it would be 6

Let’s try the same problem by using another method:
\sqrt{18}\times\sqrt{2} would equal to \sqrt{36} can also be written as \sqrt{9}\times\sqrt{2}\times\sqrt{2}
This also leads to the answer of 6

For \sqrt{15}\times\sqrt{45}, it would equal to \sqrt{675}
25 goes into 675 twenty-seven times
Since 5 is the square root of 25, \sqrt{675} can be written as 5\sqrt{27}
This can be further simplified into 15\sqrt{3}

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