1)a(x-5)-7(5-x)=a(x-5)+7(x-5)=(x-5)(a+7)
24aˇ3bˇ4c-12aˇ2bˇ4cˇ2+6aˇ2bˇ3=6aˇ2.bˇ3(4abc-2bcˇ2 +1)
ab-ac+bd-cd-b+c=a(b-c)+d(b-c)-(b-c)=(b-c)(a+d-1)
x³+x²z-2xz²-2z³=x²(x+z)-2z²(x+z)=(x+z)(x²-2z²)=(x+z)(x+√2z)(x-√2z)
2ac+6bc-4ad-12bd=2c(a+3b)-4d(a+3b)=(a+3b)(2c-4d)=
=2(a+3b)(c-2d)
2)y(y-5)-3y(5-y)²=0
y(y-5)-3y(y-5)²=0
(y-5)(y-3y²+15y)=0
a)y-5=0, y=5
b)y-3y²+15y=16y-3y²=y(16-3y)=0, y=0, y=16/3
Otvet: y=5, y=0, y=16/3
3)8ˇ5+2ˇ11=(2ˇ3)ˇ5+2ˇ11=2ˇ15+2ˇ11=2ˇ11(2ˇ4+1)=2ˇ11(16+1)=
=2048.17