Solve the Quartic Equation: x⁴ - x³ = 2x²

Quartic Equations with Factoring Techniques

What is the value of x?

x4x3=2x2 x^4-x^3=2x^2

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:07 Let's find the value of X.
00:10 First, arrange the equation so the right side equals zero.
00:19 Next, factor the equation, starting with the X squared term.
00:30 Now, take out the common factor from the parentheses.
00:40 We're looking for solutions that make each factor equal zero.
00:47 Great! This gives us one solution.
00:51 Now, let's find the second solution.
00:55 Factor using trinomials. Pay attention to the coefficients.
01:02 We need two numbers that add up to B, which is negative one.
01:07 And their product should equal C, which is negative two.
01:12 These numbers fit perfectly. Let's substitute them into our multiplication.
01:18 Again, find solutions that make each factor zero.
01:22 And that's how we solve the problem. Well done!

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

What is the value of x?

x4x3=2x2 x^4-x^3=2x^2

2

Step-by-step solution

To solve the problem x4x3=2x2 x^4 - x^3 = 2x^2 , let's proceed as follows:

  • Step 1: Set the equation to zero.
    x4x32x2=0 x^4 - x^3 - 2x^2 = 0
  • Step 2: Factor out the greatest common factor.
    The common factor among all terms is x2 x^2 .
    Factoring out x2 x^2 gives:
    x2(x2x2)=0 x^2(x^2 - x - 2) = 0
  • Step 3: Solve the factors.
    This equation breaks into two factors that can be solved separately:
    • x2=0 x^2 = 0
    • x2x2=0 x^2 - x - 2 = 0
  • Step 4: Solve x2=0 x^2 = 0 .
    Since x2=0 x^2 = 0 , we get:
    x=0 x = 0
  • Step 5: Solve x2x2=0 x^2 - x - 2 = 0 .
    This can be factored further. We look for two numbers that multiply to 2-2 and add up to 1-1.
    These numbers are 2-2 and 11, so we factor as:
    (x2)(x+1)=0 (x - 2)(x + 1) = 0
  • Step 6: Solve the quadratic factors.
    Set each factor equal to zero:
    • x2=0x=2 x - 2 = 0 \Rightarrow x = 2
    • x+1=0x=1 x + 1 = 0 \Rightarrow x = -1

The solutions to the equation x4x3=2x2 x^4 - x^3 = 2x^2 are x=1,0,2 x = -1, 0, 2 .

Therefore, the correct answer is:

x=1,2,0 x = -1, 2, 0

3

Final Answer

x=1,2,0 x=-1,2,0

Key Points to Remember

Essential concepts to master this topic
  • Rule: Move all terms to one side to set equation equal to zero
  • Technique: Factor out GCF first: x2(x2x2)=0 x^2(x^2 - x - 2) = 0
  • Check: Substitute each solution back into original equation to verify ✓

Common Mistakes

Avoid these frequent errors
  • Dividing both sides by x without considering x = 0
    Don't divide x4x3=2x2 x^4 - x^3 = 2x^2 by x to get x3x2=2x x^3 - x^2 = 2x = you lose the solution x = 0! Division by x is only valid when x ≠ 0. Always factor out common factors instead of dividing.

Practice Quiz

Test your knowledge with interactive questions

Break down the expression into basic terms:

\( 4x^2 + 6x \)

FAQ

Everything you need to know about this question

Why do I need to move everything to one side first?

+

Setting the equation to zero lets you use the Zero Product Property: if a×b=0 a \times b = 0 , then either a=0 a = 0 or b=0 b = 0 (or both). This is essential for factoring!

How do I know what to factor out as the GCF?

+

Look for the highest power of x that appears in every term. Here, x4 x^4 , x3 x^3 , and x2 x^2 all contain at least x2 x^2 , so factor out x2 x^2 .

What if I can't factor the quadratic part?

+

If the quadratic x2x2 x^2 - x - 2 doesn't factor nicely, use the quadratic formula: x=b±b24ac2a x = \frac{-b \pm \sqrt{b^2-4ac}}{2a} . But always try factoring first—it's usually faster!

Why does x = 0 count as a solution twice?

+

Actually, x=0 x = 0 is a double root because we factored out x2 x^2 . In polynomial terms, it has multiplicity 2, but we only list it once in our final answer.

How can I check if my three solutions are correct?

+

Substitute each value into the original equation x4x3=2x2 x^4 - x^3 = 2x^2 :

  • x=0 x = 0 : 00=0 0 - 0 = 0
  • x=2 x = 2 : 168=8 16 - 8 = 8
  • x=1 x = -1 : 1+1=2 1 + 1 = 2

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Algebraic Technique questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations