А) =(y-3)²
б) =(3x)³-y³=(3x-y)(9x²+3xy+y²)
в) a^4-625=(a²)²-25²=(a²-25)(a²+25)=(a-5)(a+5)(a²+25)
г) =3a(b-5) + 12(b-5)=3(b-5)(a+4)
д) =y^4 *(x-2)-y(x-2)=(x-2)(y^4-y)=y(x-2)(y³-1)
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5x³-5x=0
5x(x²-1)=0
x1=0; x2=-1; x3=1
64x³-16x²+x=0
x(64x²-16x+1)=0
x1=0
64x²-16x+1=0
D=256-256=0
x2=16/(64*2) =1/8
ответ x1=0 x2=1/8
x³-3x²-4x+12=0
x²(x-3)-4(x-3)=0
(x-3)(x²-4)=0
x1=0; x2=2; x3=-2