Нужно разложить на множители

1) - 4a^8b+12a^2b^3c

2) - 20x^6y-35x^6

3) 7xy-y+21x-3

4) 12x^2+6y-2x^2y-y^2

5) 16x^3-xy^2

6) a^3b-25ab^3

1) - 4a^8b+12a^2b^3c=-4a ²b (a^6-3b²c)

2) - 20x^6y-35x^6=-5x^6 (4y+7)

3) 7xy-y+21x-3=y (7x-1) + 3 (7x-1) = (7x-1) (y+3)

4) 12x^2+6y-2x^2y-y^2=6 (2x ²+y) - y (2x²+y) = (2x²+y) (6-y)

5) 16x^3-xy^2=x (16x ²-y²) = x (4x-y) (4x+y)

6) a^3b-25ab^3=ab (a ²-25b²) = ab (a-5b) (a+5b)