lesson

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If you can divide 756 by 3 using long division, you already know almost everything you need to divide algebraic expressions.
A degree-three polynomial (or cubic) has x3 as its highest power, while a degree-one divisor is a linear binomial like xβ3.
Just like standard arithmetic, polynomial division runs on a four-step loop: Divide, Multiply, Subtract, and Bring down.
πInteractive diagram
Let's see how this four-step loop works from start to finish on a complete cubic polynomial.
Step-by-Step Long Division
Let's divide 2x3β3x2β11x+6 by xβ3.
First, divide the leading terms: x2x3β=2x2. Multiply 2x2(xβ3)=2x3β6x2, subtract it to get 3x2, and bring down β11x.
πInteractive diagram
Repeating the cycle with x3x2β=3x and xβ2xβ=β2 gives a final quotient of 2x2+3xβ2 with a remainder of 0.
The most common mistake in polynomial long division is dropping signs during subtraction. When subtracting (2x3β6x2), distribute the negative to make it β2x3+6x2 before combining.
What happens if our cubic polynomial skips a power of x, like going straight from x3 to x?