1)(а-2b)*((a-2b)³-8) =(a-2b)*(a-2b-2)((a-2b)²+(a-2b)*2+4)=(a-2b)(a-2b-2)(a²-4ab+4b²+2a-4b-4)
2)(x-3y)²(x-3y)²-27x+81y =(x²-6xy+9)(x²-6xy+9) = x⁴-6x³y+9x²y²-6x³y+36x²y²-54xy³+9x²y²-54xy³+81y⁴-27x+81y=x⁴-12x³y+54x²y²-108xy³+81y⁴-27x+81y
3)(a-2b-a-2b)((a-2b)²+a²-4b²+(a+2b²))=-4b(a²-4ab+4b²+a²-4b²+a²+4ab+4b²)=-4b(3a²+4b²)
4)(2x+3y+3x-2y)((2x+3y)²-(2x+3y)(3x-2y)+(3x-2y)²)=(5x+y)(4x²+12xy+9y²-6x²-5xy+6y²+9a²-12xy+4y²)=(5x+y)(7x²+19y²-5xy)