Ruffini's rule

Ruffini’s rule is a method that simplifies the operations in a division whose divisor is x – a.
To do it, we put the coefficients of the dividend in a row and multiply the first coefficient by a and we add it to the next, and so on.

For example, if we divide    x³ -3x² + x + 2 by x – 3: 

quotient is x² + 1 and the remainder is 5

 

 

or  x⁴ – 16 by x + 2:

     quotient is x³ – 2x² +4x – 8 and the remainder is 0