Решение:
а) $$-12x^4y^3 = (-3x^2y) \cdot (4x^2y^2)$$, $$-12x^4y^3 = (3x^3y^3) \cdot (-4x)$$, $$-12x^4y^3 = (6x^4) \cdot (-2y^3)$$
б) $$-12x^4y^3 = 2 \cdot (-3x) \cdot (2x^3y^3)$$, $$-12x^4y^3 = (-1) \cdot 4x^2 \cdot (3x^2y^3)$$, $$-12x^4y^3 = 2x \cdot (-2y) \cdot (3x^3y^2)$$
Ответ: а) $$-12x^4y^3 = (-3x^2y) \cdot (4x^2y^2)$$, $$-12x^4y^3 = (3x^3y^3) \cdot (-4x)$$, $$-12x^4y^3 = (6x^4) \cdot (-2y^3)$$, б) $$-12x^4y^3 = 2 \cdot (-3x) \cdot (2x^3y^3)$$, $$-12x^4y^3 = (-1) \cdot 4x^2 \cdot (3x^2y^3)$$, $$-12x^4y^3 = 2x \cdot (-2y) \cdot (3x^3y^2)$$