The result of differentiation. Suppose f(x) is a function of x. The derivative of f(x) with respect to x is expressed as d¹f(x)/dx or f¹(x). This derivative is the first derivative of f(x). The second derivative of f(x) is the derivative of the first derivative of f(x). It is expressed as d²f(x)/dx or f²(x). In general the n^th derivative of f(x) is the derivative of the (n-1)^th derivative of f(x). It is expressed as dⁿf(x)/dx or
fⁿ(x).