What is the product?

[tex]\[
\left(y^2 + 3y + 7\right)\left(8y^2 + y + 1\right)
\][/tex]

A. [tex]\[8y^4 + 24y^3 + 60y^2 + 10y + 7\][/tex]

B. [tex]\[8y^4 + 25y^3 + 4y^2 + 10y + 7\][/tex]

C. [tex]\[8y^4 + 25y^3 + 80y^2 + 7y + 7\][/tex]

D. [tex]\[8y^4 + 25y^3 + 60y^2 + 10y + 7\][/tex]



Answer :

To find the product of the two polynomials [tex]\(\left(y^2 + 3y + 7\right) \left(8y^2 + y + 1\right)\)[/tex], we'll multiply the two expressions step-by-step and combine like terms.

Step 1: Distribute [tex]\(y^2\)[/tex]:

[tex]\[ y^2 \cdot (8y^2) + y^2 \cdot (y) + y^2 \cdot (1) = 8y^4 + y^3 + y^2 \][/tex]

Step 2: Distribute [tex]\(3y\)[/tex]:

[tex]\[ 3y \cdot (8y^2) + 3y \cdot (y) + 3y \cdot (1) = 24y^3 + 3y^2 + 3y \][/tex]

Step 3: Distribute [tex]\(7\)[/tex]:

[tex]\[ 7 \cdot (8y^2) + 7 \cdot (y) + 7 \cdot (1) = 56y^2 + 7y + 7 \][/tex]

Step 4: Combine the results from steps 1, 2, and 3:

[tex]\[ 8y^4 + y^3 + y^2 + 24y^3 + 3y^2 + 3y + 56y^2 + 7y + 7 \][/tex]

Step 5: Combine like terms:

- [tex]\(8y^4\)[/tex] (the only [tex]\(y^4\)[/tex] term)
- [tex]\(1y^3 + 24y^3 = 25y^3\)[/tex]
- [tex]\(y^2 + 3y^2 + 56y^2 = 60y^2\)[/tex]
- [tex]\(3y + 7y = 10y\)[/tex]
- [tex]\(+7\)[/tex] (the constant term)

So, the combined polynomial is:

[tex]\[ 8y^4 + 25y^3 + 60y^2 + 10y + 7 \][/tex]

Therefore, the correct product is:

[tex]\[ \boxed{4} \][/tex]