-2x²(2x²+3x-2)(1+2x)(y-x)(3c-4)²=
=-2x²(2x²+3x-2)(y-x+2xy-2x²)(9c²-24c+16)=
=(-4x^4-6x³+4x²)(y-x+2xy-2x²)(9c²-24c+16)=
=(-4x^4+4x^5-8x^5y+8x^6 -6x³y+6x^4-12x^4y+12x^5 +4x²-4x³+8x³y-8x^4)(9c²-24c+16)=
=(-16x^4y-8x^5y+16x^5+8x^6-2x^4-4x³+2x³y+4x²y)(9c²-24c+16)=
=-144x^4c²y-72x^5c²y+144x^5c^2+72x^6c²-18x^4c²-36x³c²-18x^3c²y+36x²c²y +
+384x^4cy+192x^5cy-384x^5c-192x^6c+48x^4c+96x³c+48x³cy-96x²cy –
-256x^4y-128x^5y+256x^5+128x^6-32x^4-64x³-32x³y+64x²y