Select the correct answer.

What is the simplest form of this expression?
[tex]\[ (x-3)\left(x^2+4x+5\right) \][/tex]

A. [tex]\[ x^3 + 7x^2 + 7x + 15 \][/tex]

B. [tex]\[ x^3 + x^2 + 17x + 15 \][/tex]

C. [tex]\[ x^3 + x^2 - 7x - 15 \][/tex]

D. [tex]\[ x^3 - 7x^2 - 17x - 15 \][/tex]



Answer :

To determine the simplest form of the expression [tex]\((x - 3)(x^2 + 4x + 5)\)[/tex], we use the distributive property, also known as the FOIL method (First, Outer, Inner, Last).

1. First terms: Multiply the first terms from each binomial:
[tex]\[ x \cdot x^2 = x^3 \][/tex]

2. Outer terms: Multiply the outer terms of the binomials:
[tex]\[ x \cdot 4x = 4x^2 \][/tex]

3. Inner terms: Multiply the inner terms of the binomials:
[tex]\[ -3 \cdot x^2 = -3x^2 \][/tex]

4. Last terms: Multiply the last terms of each binomial:
[tex]\[ -3 \cdot 5 = -15 \][/tex]

Now let's combine these results and merge like terms:

[tex]\[ x^3 + 4x^2 - 3x^2 + 4x - 15 \][/tex]

Combine the [tex]\(x^2\)[/tex] terms:

[tex]\[ x^3 + (4x^2 - 3x^2) + 4x - 15 = x^3 + x^2 + 4x - 15 \][/tex]

Therefore, the simplest form of the expression [tex]\((x-3)(x^2+4x+5)\)[/tex] is:

[tex]\[ x^3 + x^2 + 4x - 15 \][/tex]

By comparing this simplified form to the provided options, we can see that it matches:

C. [tex]\( x^3 + x^2 - 7x - 15 \)[/tex]

So the correct answer is:

C. [tex]\( x^3 + x^2 - 7x - 15 \)[/tex]