A quadratic polynomial F ∈ K [ X 1 , … , X n ] {\displaystyle {}F\in K[X_{1},\ldots ,X_{n}]} over a field K {\displaystyle {}K} is a polynomial of degree 2 {\displaystyle {}2} ; that is, an expression of the form
where a i j , b i , c ∈ K {\displaystyle {}a_{ij},b_{i},c\in K} .
![{\displaystyle {}F\in K[X_{1},\ldots ,X_{n}]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/eb9907eef7712dd23f5765db372457691aa7d626)
over a
field
is a polynomial of
degree
; that is, an expression of the form
.
