Unlock The Mystery: Factors Of 6x^3+6

by Alex Johnson 38 views

Ever stared at a polynomial and wondered what its hidden building blocks are? Polynomial factorization is like a detective story for mathematicians, and today, we're going to crack the case of 6x3+66x^3+6. We'll dive deep into the world of algebraic expressions, exploring different techniques to uncover the factors of this specific expression. Get ready to sharpen your mathematical minds as we break down this problem step-by-step, making sure everyone can follow along, from beginners to seasoned algebra enthusiasts. Our journey will involve understanding key concepts like the sum of cubes and polynomial division, ensuring that by the end, you'll feel confident in your ability to tackle similar problems. We'll also discuss why certain options are correct and others are not, providing a comprehensive understanding of the process. So, grab your metaphorical magnifying glass, and let's get started on this exciting mathematical investigation!

The Quest for Factors: Unpacking 6x3+66x^3+6

Our central mission is to find the factors of the expression 6x3+66x^3+6. Before we jump into the options, let's first simplify and understand the expression itself. The first step in any factorization problem is to look for common factors among the terms. In 6x3+66x^3+6, we can clearly see that both 6x36x^3 and 66 share a common factor of 6. Factoring this out, we get: 6(x3+1)6(x^3+1). Now, the problem is reduced to finding the factors of x3+1x^3+1. This expression, x3+1x^3+1, is a classic example of a sum of cubes. The general formula for the sum of cubes is a3+b3=(a+b)(a2βˆ’ab+b2)a^3 + b^3 = (a+b)(a^2 - ab + b^2). In our case, a=xa=x and b=1b=1 (since 13=11^3=1). Applying the formula, we can factor x3+1x^3+1 as follows: x3+13=(x+1)(x2βˆ’x(1)+12)=(x+1)(x2βˆ’x+1)x^3+1^3 = (x+1)(x^2 - x(1) + 1^2) = (x+1)(x^2-x+1). Therefore, the complete factorization of 6x3+66x^3+6 is 6(x+1)(x2βˆ’x+1)6(x+1)(x^2-x+1). Now that we have the fully factored form, we can easily identify its factors by looking at the options provided. This systematic approach ensures we don't miss any crucial steps and arrive at the correct solution. Remember, recognizing patterns like the sum of cubes is a superpower in algebra!

Evaluating the Options: A Factor-by-Factor Analysis

With the factored form of 6x3+66x^3+6 established as 6(x+1)(x2βˆ’x+1)6(x+1)(x^2-x+1), let's now meticulously examine each given option to determine which one is a factor. This process involves more than just matching; it's about understanding the divisibility of our original expression by each potential factor. We're essentially performing a series of checks, and only one will pass the test of being a true divisor.

Option A: xβˆ’1x-1

To check if xβˆ’1x-1 is a factor, we can use the Factor Theorem, which states that if P(a)=0P(a)=0, then xβˆ’ax-a is a factor of the polynomial P(x)P(x). For xβˆ’1x-1 to be a factor, x=1x=1 must be a root of 6x3+66x^3+6. Let's substitute x=1x=1 into the expression: 6(1)3+6=6(1)+6=6+6=126(1)^3+6 = 6(1)+6 = 6+6 = 12. Since 12β‰ 012 \neq 0, xβˆ’1x-1 is not a factor of 6x3+66x^3+6. This is a crucial distinction; if the remainder is non-zero, the expression does not divide evenly.

Option B: x+1x+1

Now, let's test x+1x+1. According to the Factor Theorem, if x=βˆ’1x=-1 is a root of 6x3+66x^3+6, then x+1x+1 is a factor. Substituting x=βˆ’1x=-1: 6(βˆ’1)3+6=6(βˆ’1)+6=βˆ’6+6=06(-1)^3+6 = 6(-1)+6 = -6+6 = 0. Since the result is 0, x+1x+1 is a factor of 6x3+66x^3+6. This aligns perfectly with our earlier factorization using the sum of cubes formula, where (x+1)(x+1) was indeed one of the resulting factors. This confirms our findings and demonstrates the power of consistent application of algebraic rules.

Option C: x2βˆ’2x+1x^2-2x+1

Option C is x2βˆ’2x+1x^2-2x+1. We can recognize this as a perfect square trinomial, (xβˆ’1)2(x-1)^2. For (xβˆ’1)2(x-1)^2 to be a factor, (xβˆ’1)(x-1) must be a factor, and we've already determined that it is not. Alternatively, we can perform polynomial division. However, a simpler check is to recall that if xβˆ’1x-1 is not a factor, then (xβˆ’1)2(x-1)^2 cannot be a factor either. Since 6x3+66x^3+6 is not divisible by xβˆ’1x-1, it certainly won't be divisible by a multiple of xβˆ’1x-1. Therefore, x2βˆ’2x+1x^2-2x+1 is not a factor.

Option D: x2+x+1x^2+x+1

Option D is x2+x+1x^2+x+1. This is a quadratic factor. We found earlier that 6x3+6=6(x+1)(x2βˆ’x+1)6x^3+6 = 6(x+1)(x^2-x+1). The quadratic factor we obtained is x2βˆ’x+1x^2-x+1, not x2+x+1x^2+x+1. To be absolutely sure, we could perform polynomial long division of 6x3+66x^3+6 by x2+x+1x^2+x+1, or observe that the roots of x2+x+1x^2+x+1 are complex, and do not correspond to roots of 6x3+66x^3+6 that would result from simple factoring. The expression x2+x+1x^2+x+1 is actually a factor of x3βˆ’1x^3-1, not x3+1x^3+1. Therefore, x2+x+1x^2+x+1 is not a factor of 6x3+66x^3+6.

The Power of Sum of Cubes: A Deeper Dive

Let's take a moment to truly appreciate the elegance of the sum of cubes formula and how it simplifies our problem. The expression x3+1x^3+1 is a prime candidate for this formula. Recall that a3+b3=(a+b)(a2βˆ’ab+b2)a^3 + b^3 = (a+b)(a^2 - ab + b^2). When we apply this to x3+1x^3+1, we are essentially identifying aa as xx and bb as 11. The formula then directly gives us (x+1)(x2βˆ’ximes1+12)(x+1)(x^2 - x imes 1 + 1^2), which simplifies to (x+1)(x2βˆ’x+1)(x+1)(x^2-x+1). This is a fundamental identity in algebra, and recognizing it is key to efficiently factoring expressions of this form. The factor (x+1)(x+1) is linear, meaning it's a first-degree polynomial. The factor (x2βˆ’x+1)(x^2-x+1) is quadratic, a second-degree polynomial. Together, these two factors, when multiplied, reconstruct x3+1x^3+1. The original expression 6x3+66x^3+6 simply has a constant factor of 66 multiplied by this sum of cubes. So, 6x3+6=6imes(x3+1)=6imes(x+1)(x2βˆ’x+1)6x^3+6 = 6 imes (x^3+1) = 6 imes (x+1)(x^2-x+1). The factors of 6x3+66x^3+6 include 66, (x+1)(x+1), (x2βˆ’x+1)(x^2-x+1), and any combination of these, such as 6(x+1)6(x+1), 6(x2βˆ’x+1)6(x^2-x+1), and (x+1)(x2βˆ’x+1)(x+1)(x^2-x+1) itself. This breakdown highlights why option B, x+1x+1, is a correct factor, as it's one of the irreducible components of the expression after extracting the constant factor. Understanding these foundational formulas not only helps in solving specific problems but also builds a robust toolkit for tackling more complex algebraic challenges in the future. It's a testament to how mathematical structures repeat and can be leveraged for simplification and understanding. The simplicity of the sum of cubes formula makes factoring such expressions almost instantaneous once recognized.

Beyond the Obvious: Why Other Options Fail

We've confirmed that x+1x+1 is a factor, but let's reinforce why the other options are not. This deepens our understanding and prevents common errors. The core idea is that for an expression P(x)P(x) to be a factor of another polynomial Q(x)Q(x), Q(x)Q(x) must be perfectly divisible by P(x)P(x), leaving no remainder. We've used the Factor Theorem and direct factorization, but let's think about potential pitfalls.

Option A, xβˆ’1x-1, fails because when we evaluate 6x3+66x^3+6 at x=1x=1, we get 1212, not 00. This means there's a remainder of 1212 when 6x3+66x^3+6 is divided by xβˆ’1x-1. Imagine trying to cut a cake into xβˆ’1x-1 slices; if x=1x=1, you're trying to divide by zero, which is undefined, or if xx is slightly more than 11, the division leaves a significant leftover piece (the remainder).

Option C, x2βˆ’2x+1x^2-2x+1, is (xβˆ’1)2(x-1)^2. If xβˆ’1x-1 isn't a factor, then (xβˆ’1)2(x-1)^2 certainly can't be. It's like saying if you can't cut a whole pizza into (xβˆ’1)(x-1) equal pieces, you definitely can't cut it into (xβˆ’1)(x-1) times (xβˆ’1)(x-1) equal pieces. The divisibility chain requires the simpler factor to be present first. Our initial factorization 6(x+1)(x2βˆ’x+1)6(x+1)(x^2-x+1) shows no component that resembles (xβˆ’1)(x-1) or its powers.

Option D, x2+x+1x^2+x+1, is a common point of confusion because it looks similar to the factor x2βˆ’x+1x^2-x+1 that we found. However, algebra is precise. The sign difference is critical. The expression x2+x+1x^2+x+1 is actually related to the difference of cubes formula, a3βˆ’b3=(aβˆ’b)(a2+ab+b2)a^3-b^3 = (a-b)(a^2+ab+b^2). Specifically, x3βˆ’1=(xβˆ’1)(x2+x+1)x^3-1 = (x-1)(x^2+x+1). Since our original expression is 6x3+66x^3+6, which contains x3+1x^3+1, not x3βˆ’1x^3-1, the factor x2+x+1x^2+x+1 is not involved. If we were to divide 6x3+66x^3+6 by x2+x+1x^2+x+1, we would not get a polynomial with a zero remainder. For example, using polynomial long division, dividing x3+1x^3+1 by x2+x+1x^2+x+1 results in xβˆ’1x-1 with a remainder of 22. Thus, 6(x3+1)6(x^3+1) divided by x2+x+1x^2+x+1 will also have a non-zero remainder.

Mastering these distinctionsβ€”recognizing the sum and difference of cubes, understanding the Factor Theorem, and being meticulous with signsβ€”are the hallmarks of strong algebraic skills. It’s these careful observations that separate correct answers from plausible-looking distractors.

Conclusion: The Winning Factor

We've journeyed through the process of factoring the polynomial 6x3+66x^3+6. By first identifying the common factor of 6, we simplified the expression to 6(x3+1)6(x^3+1). Recognizing x3+1x^3+1 as a sum of cubes, we applied the formula a3+b3=(a+b)(a2βˆ’ab+b2)a^3+b^3 = (a+b)(a^2-ab+b^2) to factor it into (x+1)(x2βˆ’x+1)(x+1)(x^2-x+1). Thus, the complete factorization of 6x3+66x^3+6 is 6(x+1)(x2βˆ’x+1)6(x+1)(x^2-x+1).

Examining the given options:

  • A. xβˆ’1x-1: Not a factor, as 6(1)3+6=12β‰ 06(1)^3+6 = 12 \neq 0.
  • B. x+1x+1: Is a factor, as 6(βˆ’1)3+6=06(-1)^3+6 = 0. This directly matches one of our derived factors.
  • C. x2βˆ’2x+1x^2-2x+1: Not a factor, as it's (xβˆ’1)2(x-1)^2, and xβˆ’1x-1 is not a factor.
  • D. x2+x+1x^2+x+1: Not a factor. This expression is related to the difference of cubes (x3βˆ’1x^3-1), not the sum of cubes (x3+1x^3+1).

Therefore, the correct answer is B. x+1x+1. This exploration highlights the importance of recognizing algebraic identities and applying fundamental theorems like the Factor Theorem. Keep practicing, and you'll become a factorization pro!

For further exploration into polynomial factorization and algebraic identities, you can visit Khan Academy's Algebra Section.