Выражение: х³-64/х²+14х+49×х²-49/х²+4х+16-77-11х/х+7

((x³-64)/(x²+14x+49))*((x²-49)/(x²+4x+16))-(77-11x)/(x+7)
1. (x³-64)/(x²+14x+49)=(x³-4³)/(x+7)²=(x-4)(x²+4x+16)/(x+7)².
2. (x²-49)/(x²+4x+16)=(x+7)(x-7)/(x²+4x+16).
3.(x-4)(x²+4x+16)(x+7)(x-7)/((x²+4x+16)(x+7)²)=
=(x-4)(x-7)/(x+7)==(x²-11x+28)/(x+7).
4. (x²-11x+28)/(x+7)-(77-11x)/(x+7)=(x²-11x+28-77+11x)/(x+7)=(x²-49)/(x+7)=
=(x+7)(x-7)/(x+7)=x-7.