trinomial
{{Short description|Polynomial that has three terms}}
{{About|mathematics|the use in taxonomy|Trinomial name|the use identifying archaeological sites in the United States|Smithsonian trinomial}}
File:Pascal_pyramid_trinomial.svg derived from coefficients in an upside-down ternary plot of the terms in the expansions of the powers of a trinomial ]]
In elementary algebra, a trinomial is a polynomial consisting of three terms or monomials.{{cite web |url=https://www.mathsisfun.com/definitions/trinomial.html | title=Definition of Trinomial | work=Math Is Fun | accessdate=16 April 2016}}
Examples of trinomial expressions
- with variables
- with variables
- with variables
- , the quadratic polynomial in standard form with variables.Quadratic expressions are not always trinomials, the expressions' appearance can vary.
- with variables, nonnegative integers and any constants.
- where is variable and constants are nonnegative integers and any constants.
Trinomial equation
A trinomial equation is a polynomial equation involving three terms. An example is the equation studied by Johann Heinrich Lambert in the 18th century.{{cite journal |first=R. M. |last=Corless |first2=G. H. |last2=Gonnet |first3=D. E. G. |last3=Hare |first4=D. J. |last4=Jerey |first5=D. E. |last5=Knuth |year=1996 |url=http://www.cs.uwaterloo.ca/research/tr/1993/03/W.pdf |title=On the Lambert W Function |journal=Advances in Computational Mathematics |volume=5 |issue=1 |pages=329–359 |doi=10.1007/BF02124750 }}
=Some notable trinomials =
- The quadratic trinomial in standard form (as from above):
::
::
- A special type of trinomial can be factored in a manner similar to quadratics since it can be viewed as a quadratic in a new variable ({{math|xn}} below). This form is factored as:
::
:where
::
a_1+a_2 &= r\\
a_1 \cdot a_2 &= s.
\end{align}
:For instance, the polynomial {{math|x2 + 3x + 2}} is an example of this type of trinomial with {{math|1=n = 1}}. The solution {{math|1=a1 = −2}} and {{math|1=a2 = −1}} of the above system gives the trinomial factorization:
::{{math|1=x2 + 3x + 2 = (x + a1)(x + a2) = (x + 2)(x + 1)}}.
:The same result can be provided by Ruffini's rule, but with a more complex and time-consuming process.
See also
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- Trinomial expansion
- Monomial
- Binomial
- Multinomial
- Simple expression
- Compound expression
- Sparse polynomial
{{div col end}}
Notes
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