Номер 1.
a)(x+5)(6-x)= =6x+30-x^ 2 -5x= =-x^ 2 +x-30 b)(3a-2)(a-5)= =3a^ 2 -2a-15a+10= =3a^ 2 -17a+10 B)(2x-7)(3x^ 2 +x-4)= =6x^ 3 -21x^ 2 +2x^ 2 -7x-8x+28= = 6x^ 3 -19x^ 2 -15x+28 r) 6y-(y-3)(y^ 2 -2)= =6y-(y^ 3 -3y^ 2 -2y+6)= = 6y-y^ 3 +3y^ 2 +2y-6= =-y^ 3 +3y^ 2 +8y-6
Номер 2.
a)(-2a^ 2 +a+2)(3a-1)= =-6a^ 3 +3a^ 2 +6a+2a^ 2 -a-2= =-6a^ 3 +5a^ 2 +5a-2 6) 2x-(x^ 2 +2)(x-8)= =2x-(x^ 3 +2x-8x^ 2 -16)= =2x-x^ 3 -2x+8x^ 2 +16= =-x^ 3 +8x^ 2 +16
Номер 3.
3x ^ 2 - (3x - 1)(x + 2) = =3x^ 2 -(3x^ 2 -x+6x-2)= =3x^ 2 -3x^ 2 +x-6x+2= = -5x + 2 при х = -3 -5^ * (-3)+2=15+2=17 ответ: 17
x²+6x-16=0
x1+x2=-6 U x1*x2=-16
x1=-8 U x2=2