binomial coefficient
(noun)
A coefficient of any of the terms in the expansion of the binomial power
(noun)
A coefficient of any of the terms in the expansion of the binomial power
Examples of binomial coefficient in the following topics:
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Total Number of Subsets
- The binomial coefficients appear as the entries of Pascal's triangle where each entry is the sum of the two above it.
- The binomial theorem describes the algebraic expansion of powers of a binomial.
- The coefficient a in the term of $ax^by^c$ is known as the binomial coefficient $n^b$ or $n^c$ (the two have the same value).
- These coefficients for varying $n$ and $b$ can be arranged to form Pascal's triangle.
- Employ the Binomial Theorem to find the total number of subsets that can be made from n elements
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Binomial Expansions and Pascal's Triangle
- The binomial theorem, which uses Pascal's triangles to determine coefficients, describes the algebraic expansion of powers of a binomial.
- Any coefficient $a$ in a term $ax^by^c$ of the expanded version is known as a binomial coefficient.
- where each value $\begin{pmatrix} n \\ k \end{pmatrix} $ is a specific positive integer known as binomial coefficient.
- For a binomial expansion with a relatively small exponent, this can be a straightforward way to determine the coefficients.
- Use the Binomial Formula and Pascal's Triangle to expand a binomial raised to a power and find the coefficients of a binomial expansion
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Binomial Expansion and Factorial Notation
- The binomial theorem describes the algebraic expansion of powers of a binomial.
- The coefficients that appear in the binomial expansion are called binomial coefficients.
- The coefficient of a term $x^{n−k}y^k$ in a binomial expansion can be calculated using the combination formula.
- Note that although this formula involves a fraction, the binomial coefficient $\begin{pmatrix} n \\ k \end{pmatrix}$ is actually an integer.
- Use factorial notation to find the coefficients of a binomial expansion
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Combinations
- The number of $k$-combinations, or $\begin{pmatrix} S \\ k \end{pmatrix}$, is also known as the binomial coefficient, because it occurs as a coefficient in the binomial formula.
- The binomial coefficient is the coefficient of the $x^k$ term in the polynomial expansion of $(1+x)^n$. $$
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Complex Numbers and the Binomial Theorem
- Powers of complex numbers can be computed with the the help of the binomial theorem.
- Recall the binomial theorem, which tells how to compute powers of a binomial like $x+y$.
- Using the binomial theorem directly, this can be written as:
- Recall that the binomial coefficients (from the 5th row of Pascal's triangle) are $1, 5, 10, 10, 5, \text{and}\, 1.$ Using the binomial theorem directly, we have:
- Connect complex numbers raised to a power to the binomial theorem
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Finding a Specific Term
- The rth term of the binomial expansion can be found with the equation: ${ \begin{pmatrix} n \\ r-1 \end{pmatrix} }{ a }^{ n-(r-1) }{ b }^{ r-1 }$.
- You might multiply each binomial out to identify the coefficients, or you might use Pascal's triangle.
- Let's go through a few expansions of binomials, in order to consider any patterns that are present in the terms.
- The coefficients of the first and last terms are both $1$ and they follow Pascal's triangle.
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Multiplying Algebraic Expressions
- When you multiply monomials, you multiply their integer coefficients together and, if they contain any of the same variables, add the exponents on those variables together.
- Multiplying two binomials is less straightforward; however, there is a method that makes the process fairly convenient.
- Outer (the "outside" terms are multiplied—i.e., the first term of the first binomial with the second term of the second)
- Inner (the "inside" terms are multiplied—i.e., the second term of the first binomial with the first term of the second)
- Remember that any negative sign on a term in a binomial should also be included in the multiplication of that term.
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Sums, Differences, Products, and Quotients
- A monomial equations has one term; a binomial has two terms; a trinomial has three terms.
- Multiplying binomials and trinomials is more complicated, and follows the FOIL method.
- FOIL is a mnemonic for the standard method of multiplying two binomials; the method may be referred to as the FOIL method.
- Outer ("outside" terms are multiplied—that is, the first term of the first binomial and the second term of the second)
- Inner ("inside" terms are multiplied—second term of the first binomial and first term of the second)
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Graphing Quadratic Equations In Standard Form
- Each coefficient in a quadratic function in standard form has an impact on the shape and placement of the function's graph.
- The coefficient $a$ controls the speed of increase (or decrease) of the quadratic function from the vertex.
- If the coefficient $a>0$, the parabola opens upward, and if the coefficient $a<0$, the parabola opens downward.
- The coefficients $b$ and $a$ together control the axis of symmetry of the parabola and the $x$-coordinate of the vertex.
- The coefficient $c$ controls the height of the parabola.
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Factoring Perfect Square Trinomials
- When a trinomial is a perfect square, it can be factored into two equal binomials.
- Note that if a binomial of the form $a+b$ is squared, the result has the following form: $(a+b)^2=(a+b)(a+b)=a^2+2ab+b^2.$ So both the first and last term are squares, and the middle term has factors of $2, $ $a$, and $b,$ where the latter are the square roots of the first and last term respectively.