Answered

How would the expression [tex]$x^3 - 64$[/tex] be rewritten using the difference of cubes?

A. [tex]$(x+4)(x^2-4x+16)$[/tex]

B. [tex][tex]$(x-4)(x^2+4x+16)$[/tex][/tex]

C. [tex]$(x-4)(x^2+16x+4)$[/tex]

D. [tex]$(x+4)(x^2-4x-16)$[/tex]



Answer :

To rewrite the expression [tex]\(x^3 - 64\)[/tex] using the difference of cubes, we need to recognize that 64 can be expressed as a power of 4, specifically [tex]\(4^3\)[/tex]. The difference of cubes formula is:

[tex]\[ a^3 - b^3 = (a - b)(a^2 + ab + b^2) \][/tex]

In the given expression [tex]\(x^3 - 64\)[/tex], we can set [tex]\(a = x\)[/tex] and [tex]\(b = 4\)[/tex] since [tex]\(64 = 4^3\)[/tex].

Substituting [tex]\(a\)[/tex] and [tex]\(b\)[/tex] into the formula, we get:

[tex]\[ x^3 - 64 = x^3 - 4^3 \][/tex]

Now, applying the difference of cubes formula:

[tex]\[ x^3 - 4^3 = (x - 4)(x^2 + 4x + 16) \][/tex]

We need to compare this with the given options to identify the correct factorization:

A. [tex]\((x+4)(x^2 - 4x + 16)\)[/tex]

B. [tex]\((x-4)(x^2 + 4x + 16)\)[/tex]

C. [tex]\((x-4)(x^2 + 16x + 4)\)[/tex]

D. [tex]\((x+4)(x^2 - 4x - 16)\)[/tex]

Looking at the options, the correct factorization matches option B:

[tex]\[ (x-4)(x^2 + 4x + 16) \][/tex]

Therefore, the correct answer is:

B. [tex]\((x-4)(x^2 + 4x + 16)\)[/tex]