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Octave comes with functions for computing the derivative and the integral
of a polynomial. The functions `polyder`

and `polyint`

both return new polynomials describing the result. As an example we’ll
compute the definite integral of *p(x) = x^2 + 1* from 0 to 3.

c = [1, 0, 1]; integral = polyint (c); area = polyval (integral, 3) - polyval (integral, 0) ⇒ 12

- Function File:
**polyder***(*`p`) - Function File:
*[*`k`] =**polyder***(*`a`,`b`) - Function File:
*[*`q`,`d`] =**polyder***(*`b`,`a`) Return the coefficients of the derivative of the polynomial whose coefficients are given by the vector

`p`. If a pair of polynomials is given, return the derivative of the product. If two inputs and two outputs are given, return the derivative of the polynomial quotient`a`*`b`. The quotient numerator is in`b`/`a``q`and the denominator in`d`.**See also:**polyint, polyval, polyreduce.

- Function File:
**polyint***(*`p`) - Function File:
**polyint***(*`p`,`k`) Return the coefficients of the integral of the polynomial whose coefficients are represented by the vector

`p`. The variable`k`is the constant of integration, which by default is set to zero.

- Function File:
**polyaffine***(*`f`,`mu`) Return the coefficients of the polynomial vector

`f`after an affine transformation. If`f`is the vector representing the polynomial f(x), then

is the vector representing:`g`= polyaffine (`f`,`mu`)g(x) = f( (x -

`mu`(1)) /`mu`(2) )