Multiplying Polynomials: Find The Product Of (2x^2 + 4x - 2) And (3x + 6)

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Multiplying Polynomials: Find the Product of (2x^2 + 4x - 2) and (3x + 6)

Hey guys! Today, let's dive into a super important concept in algebra: multiplying polynomials. Specifically, we're going to tackle the question of how to find the product of (2x2+4xโˆ’2)(2x^2 + 4x - 2) and (3x+6)(3x + 6). This might seem a bit daunting at first, but trust me, once you understand the method, itโ€™s actually pretty straightforward. So, let's get started and break it down step by step!

Understanding Polynomial Multiplication

Before we jump into the specific problem, let's quickly recap what polynomials are and why multiplying them is a crucial skill. Polynomials are algebraic expressions that consist of variables and coefficients, combined using addition, subtraction, and multiplication, with non-negative integer exponents. Examples include x2+3xโˆ’5x^2 + 3x - 5, 2y3โˆ’y+12y^3 - y + 1, and, of course, the expressions we're dealing with today: (2x2+4xโˆ’2)(2x^2 + 4x - 2) and (3x+6)(3x + 6).

Multiplying polynomials is fundamental in algebra because it shows up in various contexts, from simplifying expressions to solving equations and even in calculus. Mastering this skill will not only help you in your current math studies but also lay a solid foundation for more advanced topics. We often use the distributive property when multiplying polynomials, which is the key to our solution today. Remember, the distributive property states that a(b+c)=ab+aca(b + c) = ab + ac. We'll be applying this property multiple times to ensure every term in the first polynomial is multiplied by every term in the second polynomial.

Think of it like this: each term in the first polynomial needs to "shake hands" with every term in the second polynomial. No term should be left out! This methodical approach ensures we capture every part of the product. So, letโ€™s get our hands dirty and walk through the steps to multiply these polynomials. Weโ€™ll break it down into manageable chunks to make it super clear and easy to follow. By the end of this section, youโ€™ll not only know how to multiply these specific polynomials but also have a solid understanding of the general process.

Step-by-Step Solution

Now, let's get to the heart of the matter: finding the product of (2x2+4xโˆ’2)(2x^2 + 4x - 2) and (3x+6)(3x + 6). We'll do this by carefully applying the distributive property, ensuring each term in the first polynomial is multiplied by each term in the second.

Step 1: Distribute the First Term

First, we'll take the first term of the first polynomial, which is 2x22x^2, and multiply it by each term in the second polynomial (3x+6)(3x + 6).

  • 2x2โˆ—3x=6x32x^2 * 3x = 6x^3
  • 2x2โˆ—6=12x22x^2 * 6 = 12x^2

So, the result of distributing 2x22x^2 is 6x3+12x26x^3 + 12x^2.

Step 2: Distribute the Second Term

Next, we move on to the second term in the first polynomial, which is 4x4x, and again multiply it by each term in the second polynomial (3x+6)(3x + 6).

  • 4xโˆ—3x=12x24x * 3x = 12x^2
  • 4xโˆ—6=24x4x * 6 = 24x

This gives us 12x2+24x12x^2 + 24x.

Step 3: Distribute the Third Term

Finally, we take the third term from the first polynomial, โˆ’2-2, and multiply it by each term in the second polynomial (3x+6)(3x + 6).

  • โˆ’2โˆ—3x=โˆ’6x-2 * 3x = -6x
  • โˆ’2โˆ—6=โˆ’12-2 * 6 = -12

Which results in โˆ’6xโˆ’12-6x - 12.

Step 4: Combine the Results

Now that we've distributed each term, we need to combine all the results we've obtained:

(6x3+12x2)+(12x2+24x)+(โˆ’6xโˆ’12)(6x^3 + 12x^2) + (12x^2 + 24x) + (-6x - 12)

Step 5: Simplify by Combining Like Terms

To simplify, we combine like terms, which are terms with the same variable and exponent.

  • x3x^3 terms: We have only one x3x^3 term, which is 6x36x^3.
  • x2x^2 terms: We have two x2x^2 terms: 12x212x^2 and 12x212x^2. Adding them gives us 24x224x^2.
  • xx terms: We have two xx terms: 24x24x and โˆ’6x-6x. Combining them yields 18x18x.
  • Constant terms: We have only one constant term, which is โˆ’12-12.

The Final Product

Putting it all together, the final product of (2x2+4xโˆ’2)(2x^2 + 4x - 2) and (3x+6)(3x + 6) is:

6x3+24x2+18xโˆ’126x^3 + 24x^2 + 18x - 12

And there you have it! We've successfully multiplied the two polynomials. Remember, the key is to take it step by step, ensuring you distribute each term properly and combine like terms at the end. This methodical approach will help you tackle any polynomial multiplication problem with confidence. Next, we'll explore some common mistakes to avoid and then wrap up with some practice problems to solidify your understanding.

Common Mistakes to Avoid

Multiplying polynomials can sometimes be tricky, and it's easy to make mistakes if you're not careful. But don't worry, guys! Weโ€™re going to highlight some common pitfalls so you can dodge them like a pro. Knowing these mistakes ahead of time will save you a lot of headaches and ensure you get the correct answer every time.

Forgetting to Distribute to All Terms

One of the most frequent errors is not distributing a term to all the terms in the other polynomial. Remember, every term in the first polynomial needs to be multiplied by every term in the second polynomial. If you miss even one multiplication, your final answer will be incorrect. For instance, when multiplying (2x2+4xโˆ’2)(2x^2 + 4x - 2) by (3x+6)(3x + 6), you need to make sure 2x22x^2 is multiplied by both 3x3x and 66, and so on for the other terms. A good way to prevent this is to double-check your work and ensure you've accounted for each term-to-term multiplication.

Incorrectly Combining Like Terms

Another common mistake is combining like terms improperly. Remember, like terms have the same variable raised to the same power. For example, 12x212x^2 and 12x212x^2 are like terms, but 12x212x^2 and 24x24x are not. When combining like terms, only add or subtract the coefficients (the numbers in front of the variables), not the exponents. So, 12x2+12x2=24x212x^2 + 12x^2 = 24x^2, but you canโ€™t combine these with the 24x24x term. Mixing up these terms will lead to an incorrect final expression.

Sign Errors

Pay close attention to the signs (positive and negative) of each term. A small sign error can throw off the entire calculation. For example, when multiplying โˆ’2-2 by 3x3x, the result is โˆ’6x-6x, not 6x6x. Similarly, when multiplying โˆ’2-2 by 66, you get โˆ’12-12. Always double-check your signs at each step. It might seem tedious, but itโ€™s much better to be thorough than to make a mistake that could have been easily avoided.

Rushing Through the Process

Polynomial multiplication can be a multi-step process, and itโ€™s tempting to rush through it to save time. However, rushing often leads to mistakes. Take your time, write each step clearly, and double-check your work as you go. Breaking the problem down into smaller, manageable steps makes it easier to keep track of everything and reduces the likelihood of errors. Remember, accuracy is more important than speed when youโ€™re learning a new skill.

By being aware of these common mistakes, you can actively avoid them and improve your accuracy in polynomial multiplication. Now that weโ€™ve covered what to watch out for, letโ€™s solidify your understanding with some practice problems.

Practice Problems

Okay, guys, now that we've walked through the solution and highlighted common mistakes, it's time to put your knowledge to the test! Practice is key to mastering polynomial multiplication, so let's dive into a few more examples. Working through these problems will help you solidify your understanding and build confidence.

Problem 1:

Multiply (x+3)(x + 3) and (2xโˆ’1)(2x - 1).

Solution:

  1. Distribute xx: xโˆ—2x=2x2x * 2x = 2x^2 and xโˆ—โˆ’1=โˆ’xx * -1 = -x
  2. Distribute 33: 3โˆ—2x=6x3 * 2x = 6x and 3โˆ—โˆ’1=โˆ’33 * -1 = -3
  3. Combine the results: 2x2โˆ’x+6xโˆ’32x^2 - x + 6x - 3
  4. Simplify by combining like terms: 2x2+5xโˆ’32x^2 + 5x - 3

Problem 2:

Find the product of (3xโˆ’2)(3x - 2) and (x2+4xโˆ’5)(x^2 + 4x - 5).

Solution:

  1. Distribute 3x3x: 3xโˆ—x2=3x33x * x^2 = 3x^3, 3xโˆ—4x=12x23x * 4x = 12x^2, and 3xโˆ—โˆ’5=โˆ’15x3x * -5 = -15x
  2. Distribute โˆ’2-2: โˆ’2โˆ—x2=โˆ’2x2-2 * x^2 = -2x^2, โˆ’2โˆ—4x=โˆ’8x-2 * 4x = -8x, and โˆ’2โˆ—โˆ’5=10-2 * -5 = 10
  3. Combine the results: 3x3+12x2โˆ’15xโˆ’2x2โˆ’8x+103x^3 + 12x^2 - 15x - 2x^2 - 8x + 10
  4. Simplify by combining like terms: 3x3+10x2โˆ’23x+103x^3 + 10x^2 - 23x + 10

Problem 3:

Multiply (x2โˆ’2x+1)(x^2 - 2x + 1) and (x+4)(x + 4).

Solution:

  1. Distribute x2x^2: x2โˆ—x=x3x^2 * x = x^3 and x2โˆ—4=4x2x^2 * 4 = 4x^2
  2. Distribute โˆ’2x-2x: โˆ’2xโˆ—x=โˆ’2x2-2x * x = -2x^2 and โˆ’2xโˆ—4=โˆ’8x-2x * 4 = -8x
  3. Distribute 11: 1โˆ—x=x1 * x = x and 1โˆ—4=41 * 4 = 4
  4. Combine the results: x3+4x2โˆ’2x2โˆ’8x+x+4x^3 + 4x^2 - 2x^2 - 8x + x + 4
  5. Simplify by combining like terms: x3+2x2โˆ’7x+4x^3 + 2x^2 - 7x + 4

Working through these examples should give you a good feel for the process of multiplying polynomials. Remember to take your time, distribute carefully, and double-check your work. The more you practice, the more comfortable and confident you'll become with these types of problems. And hey, if you stumble along the way, that's totally okay! Learning is all about making mistakes and figuring out how to fix them. So, keep at it, and you'll get there!

Conclusion

Alright, guys, we've reached the end of our polynomial multiplication journey for today! We've covered a lot, from understanding the basics of polynomial multiplication to walking through a step-by-step solution, avoiding common mistakes, and tackling some practice problems. The key takeaway here is that multiplying polynomials might seem intimidating at first, but with a methodical approach and plenty of practice, it's a skill you can definitely master.

Remember, the distributive property is your best friend in this process. Make sure every term in the first polynomial gets multiplied by every term in the second polynomial. Keep a close eye on those signs and take your time to combine like terms correctly. Rushing through can lead to errors, so itโ€™s always better to be thorough and double-check your work.

Practice is what makes perfect, so don't hesitate to work through more examples. You can find plenty of resources online and in textbooks. The more you practice, the more natural this process will become. And remember, it's okay to make mistakes along the way. Mistakes are learning opportunities in disguise!

Whether you're studying for a test, working on a homework assignment, or just brushing up on your algebra skills, I hope this guide has been helpful. Keep practicing, stay patient, and before you know it, you'll be multiplying polynomials like a pro. Happy math-ing, and I'll catch you in the next lesson! Keep up the great work, guys!