(3+x)(x-3)-(6+x²)=(x+3)(x-3)-6-x²=x²-9-6-x²=-15
(3+х)(х-3)-(6+х²)=(х+3)(х-3)-6-х²=х²-9-6-х²= -15.
формула (а-б)(а+б)=а²-б².
(3+x)(x-3)-(6+x²)=(x+3)(x-3)-6-x²=x²-9-6-x²=-15
(3+х)(х-3)-(6+х²)=(х+3)(х-3)-6-х²=х²-9-6-х²= -15.
формула (а-б)(а+б)=а²-б².