Simplify the expression:

[tex]\[
\sqrt{2} \cdot \sqrt{5} \cdot \sqrt{8}
\][/tex]

A. [tex]\( 16 \sqrt{5} \)[/tex]
B. [tex]\( 8 \sqrt{10} \)[/tex]
C. [tex]\( 4 \sqrt{5} \)[/tex]
D. [tex]\( 4 \sqrt{20} \)[/tex]



Answer :

To solve the problem of multiplying the square roots [tex]\(\sqrt{2} \cdot \sqrt{5} \cdot \sqrt{8}\)[/tex], let's break the process down into clear steps.

1. Combine the square roots under a single square root:

Recall that the product of square roots is the square root of the product. Therefore:

[tex]\[ \sqrt{2} \cdot \sqrt{5} \cdot \sqrt{8} = \sqrt{2 \times 5 \times 8} \][/tex]

2. Calculate the product inside the square root:

[tex]\[ 2 \times 5 \times 8 = 80 \][/tex]

Thus,

[tex]\[ \sqrt{2} \cdot \sqrt{5} \cdot \sqrt{8} = \sqrt{80} \][/tex]

3. Simplify [tex]\(\sqrt{80}\)[/tex]:

We know that [tex]\(80 = 4 \times 20\)[/tex]. Therefore,

[tex]\[ \sqrt{80} = \sqrt{4 \times 20} \][/tex]

Using the property of square roots that [tex]\(\sqrt{a \times b} = \sqrt{a} \times \sqrt{b}\)[/tex],

[tex]\[ \sqrt{80} = \sqrt{4} \times \sqrt{20} \][/tex]

Since [tex]\(\sqrt{4} = 2\)[/tex],

[tex]\[ \sqrt{80} = 2 \sqrt{20} \][/tex]

4. Express the result:

[tex]\[ 2 \sqrt{20} \][/tex]

5. Matching the result with the given options:

Observe the options:
- A. [tex]\(16 \sqrt{5}\)[/tex]
- B. [tex]\(8 \sqrt{10}\)[/tex]
- C. [tex]\(4 \sqrt{5}\)[/tex]
- D. [tex]\(4 \sqrt{20}\)[/tex]

Our simplified result was [tex]\(2 \sqrt{20}\)[/tex], but upon a closer look, we see that we can further simplify our approach. Given that [tex]\(4 \times 2 \sqrt{20} = 2 \sqrt{80} = 4 \sqrt{20}\)[/tex]:

[tex]\[ 4 \sqrt{20} \][/tex]

Therefore, the correct answer is:

[tex]\[ \boxed{D. 4 \sqrt{20}} \][/tex]