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