Q[a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,u]
{
p*q+l*u,o*q+k*u,j*q+f*u,i*q+e*u,l*o-k*p,j*l-f*p,i*l-e*p,j*k-f*o,i*k-e*o,f*i-e*j
}