Giải câu 3 trang 29 toán VNEN 8 tập 1.
a) (4x + 4xy + y) : (2x + y) = (2x + y) : (2x + y) = 2x + y;
b) (27x + 1) : (3x + 1) = (3x + 1)(9x - 3x + 1) : (3x + 1) = 9x - 3x + 1;
c) (x - 6xy + 9y) : (3y – x) = (x – 3y) : [-(x – 3y)] = -(x – 3y);
d) (8x - 1) : (4x + 2x + 1) = (2x – 1)(4x + 2x + 1) : (4x + 2x + 1) = 2x – 1.