6ax^2 - 12ax^3= 6ax^2 (1-2x)
2a^3-8a=2a(a^2-4)=2a(a-2)(a+2)
2a^3 - 2ab^2= 2a(a^2-b^2)=2a(a-b)(a+b)
5m^2n-20mn^2=5mn(m^2-4n^2)=5mn(m-2n)(m+2n)
1-64b^2=(1-8b)(1+8b)
2x^2-3x-2=0
D=9+16=25
x1=(3-5)/4=-0.5
x2=8/4=2
2x^2-3x-2=2(x+0.5)(x-2)
3x^2+2x-1=0
D=4+12=16
x1=(-2+4)/(2*3)=1/3
x2=-6/6=-1
3x^2+2x-1=3(x- 1/3)(x+1)
x^2-x-30=0
По теореме Виета
x1=6
x2=-5
x^2-x-30=(x-6)(x+5)