A monomial is a term comprising a real number and one or more variables with whole number exponents. For instance, where x, y and z are the variables, a, b and c are the non negative powers of these variables. The constant term in this example is 1. Furthermore, a variable with exponent zero becomes equal to 1. To add or subtract two monomials, both the terms should have similar variables, with the same exponents. Monomials with different variables or similar variables with varying exponents cannot be added or subtracted; instead they combine to form a polynomial. However, monomials with different variables can by multiplied, and the resulting term will also be a monomial.
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A polynomial is a combination of two or more monomials, detached by an addition or subtraction sign. Each monomial in the expression is called a term of the polynomial. x2 + 5x + 6, and x5 - 3x + 8 are examples of polynomials. A polynomial can be a monomial, binomial or trinomial, depending upon the number of terms present in it.
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