**s** is the vector, **Q_i** is the positive definite matrix,i=1,2,3

what’s above confused me for a long time

i wrote:

maximize(quad_form(s,Q_1)-(quad_form(s,Q_2))*(quad_form(s,Q_2))/(1+quad_form(s,Q_3))):error!

maximize(quad_form(s,Q_1)-power(quad_form(s,Q_2),2)/(1+quad_form(s,Q_3))): error!

maximize(quad_form(s,Q_1)-(quad_form(s,Q_2))^2/(1+quad_form(s,Q_3))): error!

maximize(quad_form(s,Q_1)-square((quad_form(s,Q_2)))/(1+quad_form(s,Q_3))):error!