Before you study type of polynomials, you are advised to read:
Define Terms ?
Define like Terms ?
Define Unlike Terms ?
Zero Polynomial  If in a given polynomial all the coefficients are zero then it is known as the zero polynomial
Example : 0 + 0^{3}  0
Monomial  An algebraic expression which contains only one term is known as Monomial
Or we can also say that:
An expression which contains any number of like terms is known as Monomial
Example : 2x, 3x^{2}, 4t, 9p, 9pq, 21x^{2}y all are monomial because all contains only one term.
Example : 2x + 3x + 4x this is also a monomial because all are like terms.
On adding these like terms we get 9x.
And since 9x have only one term, so its called as monomial.
Binomial  An algebraic expression which contains two unlike terms is known as Binomial
Example : 2x + 3x^{2} is a Binomial, because it contains two unlike terms i.e. 2x and 3x^{2}
Example : 9pq + 11p^{2}q is a Binomial, because it contains two unlike terms i.e. 9pq and 11p^{2}q
Trinomial  An algebraic expression which contains three unlike terms is known as Trinomial
Example : 2x + 3x^{2}  5x^{3} is a Trinomial, because it contains three unlike terms i.e. 2x, 3x^{2} and 5x^{3}
Example : 12pq + 3x^{2}  11 is a Trinomial, because it contains three unlike terms i.e. 12pq, 3x^{2} and 11

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