15-25а^2-15а+35(3а+7)
15-25а^2-15а+105+245
15-25а^2-15а+350
^-что за знак?
X+2-6x+36=36-6x+6;
x=36-6x+6-36+6x-2;
x=4.
1)= (ах-ау)+(zx-zy)=a(x-y)+z(x-y)=(a+z)(x-y)
$$$$$$$$
2) =(x^2-xy)-(6x-6y)=x(x-y)-6(x-y)=(x-6)(x-y)
$$$$$$$$$
(x+y)(y+p)=xy+xp+y^2+yp.
(2-y)(3y-8)(4a^2+b^2)=
=(6y-16-3y^2+8y)(4a^2+b^2)=
=(14y-16-3y^2)(4a^2+b^2)=
=56a^2y+14b^2y-64a^2-16b^2-12a^2y^2-3b^2y^2
|[3a-b]*[a-2b]| = | [3a,a] - [3a,2b] - [b, a] +[b,2b]| =
= |3*<u>0</u>- (6)*<u>[</u>a,b] - [b,a] +2*<u>0</u>| = | - (6)*<u>[</u>a,b] + [a,b] | =
= | - (5)*<u>[</u>a,b] | =|-5*|a| *|b|*sin(π/2) | = | -5*3*4*1| = |-60| = 60
<u>( </u>в решении <u> 0</u> обозначен нулевой вектор) ,