Polynomial Division Practice Problems
The polynomial division lesson walks through the long division algorithm one column at a time. This set drills it, with every problem constructed from a known divisor, quotient and remainder so the arithmetic is guaranteed exact.
How the difficulty levels work
| Difficulty | Divisor | Dividend | What you are asked for |
|---|---|---|---|
| Easy | linear | quadratic | the remainder |
| Medium | linear | cubic | the remainder, or the quotient’s |
| Hard | quadratic | cubic | one coefficient of the linear remainder |
Easy gives a quadratic over a linear divisor, so the quotient is linear and the remainder is a single number. Two rounds of the algorithm and you are done.
Medium steps up to a cubic dividend, which means three rounds and a quadratic quotient. Half the problems ask for the remainder and half for a specific coefficient inside the quotient, so you cannot get through the set by only ever evaluating
Hard divides by a quadratic. Synthetic division does not work here, the remainder is linear rather than constant, and you have to track two terms of the divisor through every subtraction.
The identity every problem satisfies
The dividend equals divisor times quotient plus remainder, and
A worked problem
Divide
Step 1 — divide the leading terms.
Step 2 — bring down and repeat.
Step 3 — last term.
So the quotient is
Where people lose marks
- Missing-degree placeholders.
has no or term. Write it as or the columns misalign. - Subtracting only the first term. The whole product comes off, and every sign in it flips. Writing the subtraction as an addition of the negated row prevents this.
- Stopping one step early. Keep going while the running remainder’s degree is at least the divisor’s.
- Reading the quotient off the wrong row. The quotient sits above the bar; the remainder is what is left at the bottom.
Once this is fluent, synthetic division does the same job in a fraction of the writing for linear divisors, and the remainder and factor theorem skips the division entirely when the remainder is all you need.