B12: Điền vào chỗ trống
1.(_______+_______) (9x^2-_________+1) = (____)^3 + (______)^3
2.(x+_______) (______-________+16) = (____)^3 + (______)^3
3.(_______+________) (25x^2 -10x +_____) =(_____)^3 + (______)^3
4.(_____+______) (_____-6x+9)=(_____)^3 +(______)^3