# What is Coefficient: Definition and 1000 Discussions

In mathematics, a coefficient is a multiplicative factor in some term of a polynomial, a series, or any expression; it is usually a number, but may be any expression (including variables such as a, b and c). When variables appear in the coefficients, they are often called parameters, and must be clearly distinguished from those representing other variables in an expression.
For example,

2

x

2

x
+
3

{\displaystyle 2x^{2}-x+3}
, has the real coefficients 2, -1, and 3 respectively, and

a

x

2

+
b
x
+
c

{\displaystyle ax^{2}+bx+c}
, has coefficient parameters a, b, and c respectively assuming x is the variable of the equation.
The constant coefficient is the coefficient not attached to variables in an expression. For example, the constant coefficients of the expressions above are the real coefficient 3 and the parameter represented by c.
Similarly, the coefficient attached to the highest multiplicity of the variable in a polynomial is referred to as the leading coefficient. For example in the expressions above, the leading coefficients are 2 and the parameter represented by a.
The binomial coefficients occur in the expanded form of

(
x
+
y

)

n

{\displaystyle (x+y)^{n}}
, and are tabulated in Pascal's triangle.

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19. ### Coefficient of rolling resistance

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41. ### Coefficient of friction and normal force

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42. ### What is the physical dimension of transduction coefficient in photonics?

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45. ### I Coefficient of rolling friction for a lab cart

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46. ### Equation calculations about the coefficient of kinetic friction

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48. ### Effect of Surface Area on the Drag Coefficient of a Parachute

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49. ### Will this increase the Coefficient of performance of my refrigerator?

If I orient my refrigerator such that the condenser coils at the back are facing a glass door (least insulation in room, cold outdoors) will CP increase? CP=Qc/(Qh-Qc) so Qh-Qc will be smaller thus CP larger. Could this damage refrigerator?
50. ### The relationship between angle and static coefficient

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