Simplify √7 x √8, leaving your answer in exact form.

1 answer

To simplify \( \sqrt{7} \times \sqrt{8} \), we can use the property of square roots that states:

\[ \sqrt{a} \times \sqrt{b} = \sqrt{a \times b} \]

Applying this to our expression:

\[ \sqrt{7} \times \sqrt{8} = \sqrt{7 \times 8} \]

Calculating \( 7 \times 8 \):

\[ 7 \times 8 = 56 \]

So we have:

\[ \sqrt{7} \times \sqrt{8} = \sqrt{56} \]

Next, we can simplify \( \sqrt{56} \). First, we find the prime factorization of 56:

\[ 56 = 7 \times 8 = 7 \times 4 \times 2 = 7 \times 2^3 \]

Now, we can write \( \sqrt{56} \) as:

\[ \sqrt{56} = \sqrt{7 \times 2^3} = \sqrt{7} \times \sqrt{2^3} \]

The square root of \( 2^3 \) can be simplified:

\[ \sqrt{2^3} = \sqrt{2^2 \times 2} = \sqrt{2^2} \times \sqrt{2} = 2 \times \sqrt{2} \]

Combining this back, we have:

\[ \sqrt{56} = \sqrt{7} \times (2 \times \sqrt{2}) = 2\sqrt{7} \times \sqrt{2} \]

This can be rearranged as:

\[ 2 \sqrt{14} \]

Thus, the final answer, in exact form, is:

\[ \boxed{2\sqrt{14}} \]