Solving The Polynomial Equation: $(x+2)(x+3)+(x-3)(x-2)-2x(m+1)=0$

by Andrew McMorgan 67 views

Hey there, math enthusiasts of Plastik Magazine! Today, we're diving deep into a rather interesting polynomial equation: (x+2)(x+3)+(xβˆ’3)(xβˆ’2)βˆ’2x(m+1)=0(x+2)(x+3)+(x-3)(x-2)-2x(m+1) =0. This might look a bit intimidating at first glance, with its combination of squared terms and a parameter 'mm', but don't sweat it, guys! We're going to break it down step-by-step, making sure you understand every single bit of it. Our goal here is not just to find a solution, but to understand the process of simplifying and solving such algebraic expressions. This kind of problem is super common in algebra and forms the bedrock for more complex mathematical concepts. So, grab your notebooks, sharpen your pencils, and let's get cracking on this algebraic puzzle!

Expanding the Terms

The first crucial step in tackling this equation is to expand all the products. We'll start with the first two terms: (x+2)(x+3)(x+2)(x+3) and (xβˆ’3)(xβˆ’2)(x-3)(x-2). Remember the FOIL method (First, Outer, Inner, Last) or simply distribute each term in the first binomial to each term in the second. For (x+2)(x+3)(x+2)(x+3), we get xβˆ—x+xβˆ—3+2βˆ—x+2βˆ—3x*x + x*3 + 2*x + 2*3, which simplifies to x2+3x+2x+6x^2 + 3x + 2x + 6, further simplifying to x2+5x+6x^2 + 5x + 6. Now, let's look at the second pair: (xβˆ’3)(xβˆ’2)(x-3)(x-2). Applying the same logic, we get xβˆ—x+xβˆ—(βˆ’2)+(βˆ’3)βˆ—x+(βˆ’3)βˆ—(βˆ’2)x*x + x*(-2) + (-3)*x + (-3)*(-2), which simplifies to x2βˆ’2xβˆ’3x+6x^2 - 2x - 3x + 6, resulting in x2βˆ’5x+6x^2 - 5x + 6. See? Nothing too scary yet. We're systematically reducing the complexity. It's all about being methodical and not rushing the process. Each expansion is a small victory on the path to the final solution. Remember, the beauty of mathematics lies in its structure and predictability, and by following these established rules, we can unravel even the most complex-looking expressions. Keep this momentum going, and you'll be mastering these types of problems in no time!

Simplifying the Equation

Alright, so we've expanded the first two parts. Now, let's plug those back into the original equation: (x2+5x+6)+(x2βˆ’5x+6)βˆ’2x(m+1)=0(x^2 + 5x + 6) + (x^2 - 5x + 6) - 2x(m+1) = 0. Look closely at the first two expanded terms. Notice anything cool? The '+5x+5x' and the 'βˆ’5x-5x' terms are opposites! This means they will cancel each other out when we add them. This is a common trick in algebra problems – looking for terms that eliminate each other. So, x2+x2x^2 + x^2 gives us 2x22x^2, and the '+5x+5x' and 'βˆ’5x-5x' cancel out, leaving us with 0x0x, and 6+66 + 6 gives us 1212. So, the equation simplifies to 2x2+12βˆ’2x(m+1)=02x^2 + 12 - 2x(m+1) = 0. We're getting closer, folks! Now, let's deal with that last term, βˆ’2x(m+1)-2x(m+1). We need to distribute the βˆ’2x-2x into the parenthesis (m+1)(m+1). This gives us βˆ’2xβˆ—m+(βˆ’2x)βˆ—1-2x*m + (-2x)*1, which is βˆ’2xmβˆ’2x-2xm - 2x. So, our equation now becomes 2x2+12βˆ’2xmβˆ’2x=02x^2 + 12 - 2xm - 2x = 0. This is a much cleaner representation of our original problem, and it's ready for the next stage of manipulation. This simplification phase is crucial; it’s where we trim the fat and reveal the core structure of the equation. By identifying and cancelling out terms, we make the subsequent steps significantly easier. This methodical approach is a hallmark of good mathematical practice and ensures accuracy.

Rearranging into Standard Quadratic Form

Our equation is currently 2x2+12βˆ’2xmβˆ’2x=02x^2 + 12 - 2xm - 2x = 0. To solve for 'xx', especially when we have a parameter like 'mm', it's often best to rearrange the equation into the standard quadratic form: ax2+bx+c=0ax^2 + bx + c = 0. In our case, we already have the x2x^2 term. Let's group the terms involving 'xx' together. We have βˆ’2xm-2xm and βˆ’2x-2x. We can factor out an 'xx' from these terms to get x(βˆ’2mβˆ’2)x(-2m - 2). So, the equation becomes 2x2+x(βˆ’2mβˆ’2)+12=02x^2 + x(-2m - 2) + 12 = 0. Now, let's make sure our coefficients are in the standard form. The coefficient of x2x^2 is a=2a = 2. The coefficient of xx is b=(βˆ’2mβˆ’2)b = (-2m - 2). And the constant term is c=12c = 12. So, we have successfully transformed our equation into the standard quadratic form: 2x2+(βˆ’2mβˆ’2)x+12=02x^2 + (-2m - 2)x + 12 = 0. This arrangement is key because it allows us to directly apply the quadratic formula or other standard methods for solving quadratic equations. It's like organizing your tools before starting a big project; having things in the right order makes the actual work much more efficient and less prone to errors. This systematic rearrangement is a fundamental skill in algebra, and mastering it will serve you well in all your future mathematical endeavors. Keep your eyes peeled for these patterns, guys; they are the secret shortcuts to solving complex problems.

Applying the Quadratic Formula

Now that our equation is in the standard quadratic form ax2+bx+c=0ax^2 + bx + c = 0, where a=2a=2, b=βˆ’2mβˆ’2b = -2m - 2, and c=12c = 12, we can use the quadratic formula to solve for 'xx'. The quadratic formula is: x=βˆ’bΒ±b2βˆ’4ac2ax = \frac{{-b \pm \sqrt{{b^2 - 4ac}}}}{{2a}}. Let's substitute our values for aa, bb, and cc into this formula. First, let's calculate the discriminant, which is the part under the square root: b2βˆ’4acb^2 - 4ac. Plugging in our values, we get: (βˆ’2mβˆ’2)2βˆ’4(2)(12)(-2m - 2)^2 - 4(2)(12). Let's simplify this. (βˆ’2mβˆ’2)2=(βˆ’(2m+2))2=(2m+2)2=(2m)2+2(2m)(2)+22=4m2+8m+4(-2m - 2)^2 = (-(2m+2))^2 = (2m+2)^2 = (2m)^2 + 2(2m)(2) + 2^2 = 4m^2 + 8m + 4. And 4(2)(12)=964(2)(12) = 96. So, the discriminant is 4m2+8m+4βˆ’96=βˆ—βˆ—4m2+8mβˆ’924m^2 + 8m + 4 - 96 = **4m^2 + 8m - 92**. Now, let's put this back into the quadratic formula: x=βˆ’(βˆ’2mβˆ’2)Β±4m2+8mβˆ’922(2)x = \frac{{-(-2m - 2) \pm \sqrt{{4m^2 + 8m - 92}}}}{{2(2)}}. Simplifying the numerator's first part: βˆ’(βˆ’2mβˆ’2)=2m+2-(-2m - 2) = 2m + 2. And the denominator is 2(2)=42(2) = 4. So, the solutions for 'xx' are: x=2m+2Β±4m2+8mβˆ’924x = \frac{{2m + 2 \pm \sqrt{{4m^2 + 8m - 92}}}}{{4}}. We can simplify this further by noticing that we can factor out a 2 from the term 2m+22m+2, and we can also factor out a 4 from the square root term: 4m2+8mβˆ’92=4(m2+2mβˆ’23)=2m2+2mβˆ’23\sqrt{{4m^2 + 8m - 92}} = \sqrt{{4(m^2 + 2m - 23)}} = 2\sqrt{{m^2 + 2m - 23}}. Substituting this back into our equation for xx: x=2(m+1)Β±2m2+2mβˆ’234x = \frac{{2(m + 1) \pm 2\sqrt{{m^2 + 2m - 23}}}}{{4}}. Finally, we can divide both the numerator and the denominator by 2: x=(m+1)Β±m2+2mβˆ’232x = \frac{{(m + 1) \pm \sqrt{{m^2 + 2m - 23}}}}{{2}}. This is our final solution for 'xx', expressed in terms of the parameter 'mm'. It's a powerful outcome, showing how a single equation can yield different numerical answers depending on the value of 'mm'. Understanding the quadratic formula and how to apply it systematically is a cornerstone of algebra, and seeing it in action like this really solidifies the concept. Don't get discouraged if it looks complex; each part of the formula has a purpose, and breaking it down makes it manageable. This is where the magic happens, guys – transforming abstract formulas into concrete answers!

Analyzing the Discriminant

The discriminant, which we found to be 4m2+8mβˆ’924m^2 + 8m - 92 (or 4(m2+2mβˆ’23)4(m^2 + 2m - 23) in its factored form), plays a critical role in determining the nature of the solutions for 'xx'. Remember, the discriminant is the part under the square root in the quadratic formula: b2βˆ’4acb^2 - 4ac. Its value tells us whether we will have two distinct real solutions, one repeated real solution, or two complex conjugate solutions. For our equation, the discriminant is Ξ”=4m2+8mβˆ’92\Delta = 4m^2 + 8m - 92. If Ξ”>0\Delta > 0, we will have two distinct real solutions for 'xx'. This happens when 4m2+8mβˆ’92>04m^2 + 8m - 92 > 0, which simplifies to m2+2mβˆ’23>0m^2 + 2m - 23 > 0. To find the values of 'mm' for which this inequality holds, we first find the roots of the quadratic m2+2mβˆ’23=0m^2 + 2m - 23 = 0 using the quadratic formula for 'mm': m=βˆ’2Β±22βˆ’4(1)(βˆ’23)2(1)=βˆ’2Β±4+922=βˆ’2Β±962=βˆ’2Β±462=βˆ’1Β±26m = \frac{{-2 \pm \sqrt{{2^2 - 4(1)(-23)}}}}{{2(1)}} = \frac{{-2 \pm \sqrt{{4 + 92}}}}{{2}} = \frac{{-2 \pm \sqrt{{96}}}}{{2}} = \frac{{-2 \pm 4\sqrt{{6}}}}{{2}} = -1 \pm 2\sqrt{{6}}. So, if 'mm' is greater than βˆ’1+26-1 + 2\sqrt{{6}} or less than βˆ’1βˆ’26-1 - 2\sqrt{{6}}, we'll have two distinct real solutions. If Ξ”=0\Delta = 0, we have exactly one real solution (a repeated root). This occurs when m2+2mβˆ’23=0m^2 + 2m - 23 = 0, which means 'mm' must be equal to βˆ’1+26-1 + 2\sqrt{{6}} or βˆ’1βˆ’26-1 - 2\sqrt{{6}}. In this case, the square root term in our solution for 'xx' becomes zero, and x=m+12x = \frac{{m+1}}{2}. If Ξ”<0\Delta < 0, we have two complex conjugate solutions. This happens when m2+2mβˆ’23<0m^2 + 2m - 23 < 0, which is for values of 'mm' between βˆ’1βˆ’26-1 - 2\sqrt{{6}} and βˆ’1+26-1 + 2\sqrt{{6}}. The presence of 'mm' means that the nature of the solutions for 'xx' depends entirely on the specific value assigned to 'mm'. This parametric dependence is a key concept in higher mathematics, where equations often describe families of solutions rather than just single points. It’s fascinating how a single quadratic equation can transform its solution set based on the value of a parameter. Understanding the discriminant is like having a crystal ball for your quadratic equations; it tells you what kind of answers to expect before you even fully calculate them. So, pay close attention to this part, guys, because it’s a powerful analytical tool!

Conclusion

And there you have it, folks! We've successfully navigated the complexities of the equation (x+2)(x+3)+(xβˆ’3)(xβˆ’2)βˆ’2x(m+1)=0(x+2)(x+3)+(x-3)(x-2)-2x(m+1)=0. By systematically expanding, simplifying, rearranging into standard quadratic form, and finally applying the quadratic formula, we arrived at the solution: x=(m+1)Β±m2+2mβˆ’232x = \frac{{(m + 1) \pm \sqrt{{m^2 + 2m - 23}}}}{{2}}. We also explored how the discriminant, 4m2+8mβˆ’924m^2 + 8m - 92, dictates the nature of these solutions based on the value of 'mm'. This journey through algebraic manipulation demonstrates the power of fundamental mathematical principles and the elegance of structured problem-solving. Remember, every complex equation is just a series of simpler steps waiting to be unraveled. Keep practicing, stay curious, and don't hesitate to tackle new challenges. Algebra is all about building these skills step-by-step, and with each problem you solve, you're becoming a more confident and capable mathematician. Happy solving, and we'll catch you in the next one here at Plastik Magazine!