What is the following product? Assume [tex]\( x \geq 0 \)[/tex].

[tex]\[ \left(4 x \sqrt{5 x^2} + 2 x^2 \sqrt{6}\right)^2 \][/tex]

A. [tex]\( 104 x^4 + 8 x^4 \sqrt{30 x} \)[/tex]

B. [tex]\( 80 x^6 + 8 x^5 + 8 x^5 \sqrt{30} + 24 x^4 \)[/tex]

C. [tex]\( 104 x^6 \)[/tex]

D. [tex]\( 104 x^4 + 16 x^4 \sqrt{30} \)[/tex]



Answer :

To find the product [tex]\( \left(4 x \sqrt{5 x^2}+2 x^2 \sqrt{6}\right)^2 \)[/tex], let's go through the detailed steps of expanding this expression.

Given:
[tex]\[ \left(4 x \sqrt{5 x^2}+2 x^2 \sqrt{6}\right)^2 \][/tex]

We'll denote [tex]\( A = 4 x \sqrt{5 x^2} \)[/tex] and [tex]\( B = 2 x^2 \sqrt{6} \)[/tex], so our expression becomes:
[tex]\[ (A + B)^2 \][/tex]

Using the algebraic identity for expanding a square of a sum, [tex]\((A + B)^2 = A^2 + 2AB + B^2\)[/tex], we get:
[tex]\[ (A + B)^2 = (4 x \sqrt{5 x^2})^2 + 2(4 x \sqrt{5 x^2})(2 x^2 \sqrt{6}) + (2 x^2 \sqrt{6})^2 \][/tex]

Now, we can square each term:
1. Squaring [tex]\( A \)[/tex]:
[tex]\[ (4 x \sqrt{5 x^2})^2 = (4 x)^2 \cdot (\sqrt{5 x^2})^2 = 16 x^2 \cdot 5 x^2 = 80 x^4 \][/tex]

2. Finding the product [tex]\( 2AB \)[/tex]:
[tex]\[ 2 \cdot (4 x \sqrt{5 x^2}) \cdot (2 x^2 \sqrt{6}) = 2 \cdot 4 x \cdot 2 x^2 \cdot \sqrt{5 x^2} \cdot \sqrt{6} = 8 x^3 \cdot \sqrt{30 x^2} = 8 x^3 \cdot \sqrt{30 x^2} = 8 x^3 \cdot \sqrt{30 x^2} = 8 \sqrt{30} x^3 \cdot x = 16 \sqrt{30} x^3 \cdot x = 16 \sqrt{30 x^2} x^3 = 16 \sqrt{30} x^4 \][/tex]

3. Squaring [tex]\( B \)[/tex]:
[tex]\[ (2 x^2 \sqrt{6})^2 = 4 x^4 \cdot 6 = 24 x^4 \][/tex]

Adding all the parts together:
[tex]\[ 80 x^4 + 16 \sqrt{30} x^4 + 24 x^4 = 104 x^4 + 16 \sqrt{30} x^4 \][/tex]

Thus, the expansion results in:
[tex]\[ \boxed{104 x^4 + 16 \sqrt{30} x^4} \][/tex]