1.1-6ab^3+9a^2b^6
=(3ab^3-1)^2
2.49(x-2)^2- 25(x-3)^2
=[7(x-2)+5(x-3)][7(x-2)-5(x-3)]
=(7x-14+5x-15)(7x-14-5x+15)
=(12x-29)(2x+1)
1.1-6ab^3+9a^2b^6
=(3ab^3-1)^2
2.49(x-2)^2- 25(x-3)^2
=[7(x-2)+5(x-3)][7(x-2)-5(x-3)]
=(7x-14+5x-15)(7x-14-5x+15)
=(12x-29)(2x+1)