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Last updated on September 29, 2025
A polynomial expression is a type of algebraic expression that is made up of variables, constants, and exponents, combined using addition, subtraction, and multiplication.
The word polynomial is derived from two parts: ‘Poly,’ a Greek word meaning ‘many,’ and ‘nomial,’ meaning ‘term.’ Together, a polynomial means many terms. A polynomial is an expression that involves addition, subtraction, and multiplication but not division. Each term includes a variable raised to a whole-number exponent and multiplied by a coefficient.
A polynomial can be classified into several types based on the number of terms it contains. They are:
Types | Explanation | Example |
Monomial | A type of algebraic expression that has only one term | 3x, 5x2 |
Binomial | An algebraic expression with exactly two terms, which are connected by a ‘+’ or ‘-’ sign. | x + 2, 3x -5 |
Trinomial | A polynomial with three terms in an expression. | 2x2 - x + 7 |
The degree of the polynomial is the highest power of the variable in the expression.
Polynomial expressions are classified into several types based on their degree.
Types | Explanation | Example |
Constant | It has only numbers and no variables | 6, -3 |
Linear | A polynomial has a degree of 1 in the expression. | x + 3 |
Quadratic | A polynomial has degree 2 in the expression. | x2 + 3x -2 |
Cubic | A polynomial has the highest degree of 3 in the expression | x3 -5x2 + 2x |
Quartic | A polynomial has the highest power of 4 in the expression. | 12x4 - 32 |
Quintic | A polynomial has a degree of 5 in the expression. | 5x5 + 2x2 + 4 |
Simplifying a polynomial expression means combining like terms and rewriting it in a simpler form to make calculations easier. For example, 4x2 + 2x + 7 + 3x + 2x2 - x - 4
Group-like terms:
(4x2 + 2x2) + (2x + 3x - x) + (7 - 4)
Add or subtract the coefficients:
(4x2 + 2x2) = 6x2, (2x + 3x - x) = 4x, (7 - 4) = 3
Simplified Expression:
6x2 + 4x + 3
Polynomials are not limited to classroom studies; they are also used in our daily lives, often without us even realizing it. Here are some real-life applications of polynomial expressions:
Students may make some mistakes while solving polynomial expressions. Here are some common mistakes and tips to help avoid them.
Simplify the expression, 4x² + 3x + 7 + 2x² -5x +1
6x2- 2x + 8
Group-like terms (same variables):
(4x2 + 2x2) + (3x -5x) + (7 + 1)
Now simplify:
(4x2 + 2x2) = 6x2
(3x - 5x) = -2x
(7 + 1) = 8
The answer is 6x2 - 2x + 8
Add the polynomial (2x² + 4x + 3) + (x² -2x + 5)
3x2 + 2x + 8
Add like terms (same variables):
(2x2 + x2) + (4x -2x) + (3 + 5)
Now simplify:
(2x2 + x2) = 3x2
(4x -2x) = 2x
(3 + 5) = 8
The answer is 3x2 + 2x + 8
Subtract the polynomial, (5x² + 6x -2) - (3x² -4x + 1)
2x2 + 10x - 3
Distribute the minus sign:
5x2 + 6x - 2 - 3x2 + 4x - 1
Group and simplify:
(5x2 - 3x2) + (6x + 4x) + (-2 -1)
(5x2 - 3x2) = 2x2
(6x + 4x) = 10x
(-2 -1) = -3
The answer is 2x2 + 10x - 3
Multiply 3x (2x² - 4x + 5)
6x3 -12x2 + 15x
Distribute the 3x:
3x × 2x2 = 6x3
3x (-4x) = -12x2
3x × 5 = 15x
The answer is 6x3 - 12x2 + 15x
Evaluate the polynomial f(x) = 2x² -3x + 4 at x = -2
f(-2) = 18
Substitute x = -2 into the polynomial:
f(-2) = 2(-2)2 - 3(-2) + 4
f(-2) = 2(4) + 6 + 4
= 8 + 6 + 4
f(-2) = 18