1.(1)3x+3y (2)-24m²x-16n²x (3)x²-1 (4)(xy)²-1 (5)a的4次方x²-a的4次方y²
(6)3x²+6xy+3y² (7)(x-y)²+4xy (8)4a²-3b(4a-3b) (9)2x(a-2)-y(2-a)
(10)x(x+y)-y(x+y) (11)(a+b)²+2(a+b)+1 (13)4x的4次方-4x³+x² (14)x²-16ax+64a²
(15)(x-1)(x-3)+1 (16)(ab+a)+(b+1)