A transformation of a polynomial equation  which is of the form 
 where 
 and 
 are polynomials and 
 does not vanish at a root of 
. The cubic equation
 is a special case of such a transformation. Tschirnhaus (1683) showed that a polynomial
 of degree 
 can be reduced to a form in which the 
 and 
 terms have 0 coefficients.
 In 1786, E. S. Bring showed that a general quintic
 equation can be reduced to the form
In 1834, G. B. Jerrard showed that a Tschirnhaus transformation can be used to eliminate the , 
, and 
 terms for a general polynomial
 equation of degree 
.