Выполните действия

a) 3 (1+2xy) (1-2xy)

b) (a+b) ^2 - (a-b) ^2

c) (x^2-y^3) ^2

A) = (3 + 6xy) (1 - 2xy) = 3 - 6xy + 6xy - 12x^ (2) y^ (2) = 3 - 12x^ (2) y^ (2)

b) = (a + b) (a + b) - (a - b) (a + b) = a^ (2) + ab + ab + b^ (2) - a^ (2) + ab - ab - b^ (2) = a^ (2) + 2ab + b^ (2) - a^ (2) - b^ (2) = 2ab

c) = x^ (4) + x^ (2) y^ (3) - x^ (2) y^ (3) - y^ (6) = x^ (4) - y^ (6)

3 (1+2 ху) (1-2 ху) = 3 (1-4x^2y^2) = 3-12x^2y^2

(a+b) ^2 - (a-b) ^2=a^2+2ab+b^2-a^2+2ab-b^2=4ab

(x^2-y^3) ^2=x^4-2x^2y^3+y^6