Evaluate the expression:

[tex]\[
\begin{array}{r}
4x^2 - 5x + 3 \\
\times \quad (5x^2 + 3x + 2) \\
\hline
-13x^3 + 8x^2 - x + 6
\end{array}
\][/tex]

Note: Ensure all steps of the multiplication process are shown for clarity.



Answer :

Alright, let’s multiply the two polynomials [tex]\((4x^2 - 5x + 3)\)[/tex] and [tex]\((5x^2 + 3x + 2)\)[/tex] step-by-step.

Step 1: Distribute each term of the first polynomial to every term of the second polynomial.

Here’s how you can do it:

1. Multiply [tex]\(4x^2\)[/tex] by each term in [tex]\(5x^2 + 3x + 2\)[/tex]:
[tex]\[ 4x^2 \cdot 5x^2 = 20x^4 \][/tex]
[tex]\[ 4x^2 \cdot 3x = 12x^3 \][/tex]
[tex]\[ 4x^2 \cdot 2 = 8x^2 \][/tex]

2. Multiply [tex]\(-5x\)[/tex] by each term in [tex]\(5x^2 + 3x + 2\)[/tex]:
[tex]\[ -5x \cdot 5x^2 = -25x^3 \][/tex]
[tex]\[ -5x \cdot 3x = -15x^2 \][/tex]
[tex]\[ -5x \cdot 2 = -10 \][/tex]

3. Multiply [tex]\(3\)[/tex] by each term in [tex]\(5x^2 + 3x + 2\)[/tex]:
[tex]\[ 3 \cdot 5x^2 = 15x^2 \][/tex]
[tex]\[ 3 \cdot 3x = 9x \][/tex]
[tex]\[ 3 \cdot 2 = 6 \][/tex]

Step 2: Sum up all the terms.

Now, write down all the obtained terms and group them by the same powers of [tex]\(x\)[/tex]:
[tex]\[ 20x^4 + 12x^3 + 8x^2 - 25x^3 - 15x^2 -10x + 15x^2 + 9x + 6 \][/tex]

Combine the like terms:
- For [tex]\(x^4\)[/tex]: [tex]\(20x^4\)[/tex]
- For [tex]\(x^3\)[/tex]: [tex]\(12x^3 - 25x^3 = -13x^3\)[/tex]
- For [tex]\(x^2\)[/tex]: [tex]\(8x^2 - 15x^2 + 15x^2 = 8x^2\)[/tex]
- For [tex]\(x\)[/tex]: [tex]\(-10x + 9x = -x\)[/tex]
- Constants: [tex]\(6\)[/tex]

So, the resulting polynomial is:
[tex]\[ 20x^4 - 13x^3 + 8x^2 - x + 6 \][/tex]

This is the final answer:
[tex]\[ 20x^4 - 13x^3 + 8x^2 - x + 6 \][/tex]