Coefficient

A numerical factor in an algebraic expression, a known factor in front of a power of an unknown or a constant factor multiplying a variable quantity. Thus, the coefficient in the monomial $-(3/4)a^2b^2$ is $-3/4$; in the equation $x^2+2px+q=0$, the coefficient of $x^2$ is $1$, while that of $x$ is $2p$; in the formula for the length of a circumference $l=2\pi r$, the coefficient is $2\pi$. In the equation of a straight line $y=kx+b$, the number $k$, which represents the tangent of the angle at which the straight line is inclined to the $x$-axis, is called the angular coefficient.