Найдите пропущенные значения:

\(\displaystyle \small(3s^{\,2}tu^{\,7}-4s^{\,15}t^{\,2}u^{\,3}+7st^{\,7})(3stu-4tu^{\,8})=\)

\(\displaystyle \small =\)[?||-][ ]\(\displaystyle \small(3stu-4tu^{\,8})\)[?|+|-][ ]\(\displaystyle \small (3stu-4tu^{\,8})\)[?|+|-][ ]\(\displaystyle \small (3stu-4tu^{\,8})\)