What is the binomial expansion of [tex]$(x+2)^4$[/tex]?

A. [tex]x^4 + 4x^3 + 6x^2 + 4x + 1[/tex]

B. [tex]8x^3 + 24x^2 + 32x[/tex]

C. [tex]x^4 + 8x^3 + 24x^2 + 32x + 16[/tex]

D. [tex]2x^4 + 8x^3 + 12x^2 + 8x + 2[/tex]



Answer :

To perform the binomial expansion of [tex]\((x + 2)^4\)[/tex], we will use the Binomial Theorem. The Binomial Theorem states that:

[tex]\[ (a + b)^n = \sum_{k=0}^{n} \binom{n}{k} a^{n-k} b^k \][/tex]

For our particular case [tex]\((x + 2)^4\)[/tex], let's set [tex]\(a = x\)[/tex], [tex]\(b = 2\)[/tex], and [tex]\(n = 4\)[/tex]. Applying the binomial theorem, we get:

[tex]\[ (x + 2)^4 = \sum_{k=0}^{4} \binom{4}{k} x^{4-k} \cdot 2^k \][/tex]

Let's break this down term by term:

1. For [tex]\(k = 0\)[/tex]:
[tex]\[ \binom{4}{0} x^{4-0} \cdot 2^0 = 1 \cdot x^4 \cdot 1 = x^4 \][/tex]

2. For [tex]\(k = 1\)[/tex]:
[tex]\[ \binom{4}{1} x^{4-1} \cdot 2^1 = 4 \cdot x^3 \cdot 2 = 8x^3 \][/tex]

3. For [tex]\(k = 2\)[/tex]:
[tex]\[ \binom{4}{2} x^{4-2} \cdot 2^2 = 6 \cdot x^2 \cdot 4 = 24x^2 \][/tex]

4. For [tex]\(k = 3\)[/tex]:
[tex]\[ \binom{4}{3} x^{4-3} \cdot 2^3 = 4 \cdot x \cdot 8 = 32x \][/tex]

5. For [tex]\(k = 4\)[/tex]:
[tex]\[ \binom{4}{4} x^{4-4} \cdot 2^4 = 1 \cdot 1 \cdot 16 = 16 \][/tex]

Adding all these terms together, we get:

[tex]\[ x^4 + 8x^3 + 24x^2 + 32x + 16 \][/tex]

Therefore, the binomial expansion of [tex]\((x + 2)^4\)[/tex] is:

[tex]\[ x^4 + 8x^3 + 24x^2 + 32x + 16 \][/tex]

The correct answer from the given choices is:

[tex]\[ x^4 + 8x^3 + 24x^2 + 32x + 16 \][/tex]