Polynomial Addition and Subtraction Math Example 2

Follow the full solution, then compare it with the other examples linked below.

Example 2

medium
Subtract (5x3βˆ’2x2+x)βˆ’(3x3+x2βˆ’4x+2)(5x^3 - 2x^2 + x) - (3x^3 + x^2 - 4x + 2).

Solution

  1. 1
    Step 1: Distribute the negative sign: 5x3βˆ’2x2+xβˆ’3x3βˆ’x2+4xβˆ’25x^3 - 2x^2 + x - 3x^3 - x^2 + 4x - 2.
  2. 2
    Step 2: Group like terms: (5x3βˆ’3x3)+(βˆ’2x2βˆ’x2)+(x+4x)+(βˆ’2)(5x^3 - 3x^3) + (-2x^2 - x^2) + (x + 4x) + (-2).
  3. 3
    Step 3: Combine: 2x3βˆ’3x2+5xβˆ’22x^3 - 3x^2 + 5x - 2.
  4. 4
    Check: At x=1x = 1: (5βˆ’2+1)βˆ’(3+1βˆ’4+2)=4βˆ’2=2(5-2+1) - (3+1-4+2) = 4 - 2 = 2 and 2βˆ’3+5βˆ’2=22-3+5-2 = 2 βœ“

Answer

2x3βˆ’3x2+5xβˆ’22x^3 - 3x^2 + 5x - 2
When subtracting polynomials, distribute the negative sign to every term in the second polynomial before combining like terms. A common mistake is forgetting to change the sign of all terms.

About Polynomial Addition and Subtraction

Adding or subtracting polynomials by combining like termsβ€”terms with the same variable raised to the same power.

Learn more about Polynomial Addition and Subtraction β†’

More Polynomial Addition and Subtraction Examples