学以致用计算: (教科书第102页第1题) ( 1) (2 x 1) (x 3);2 x 2 7 x 3 2 2 ( 2) (m 2n) (3n m); 6n mn m2 ( 3) (a 1) ; a 2 2a 1 ( 4) (a 3b) (a 3b); a 2 9b 2 3 2 (2 x 2 1) (x 4); ( 5) 2 x 8x x 4
练习1
( 6) (x2 2 x 3) (2 x 5) . 2 x 3 x 2 4 x 15
学以致用计算: (教科书第102页第1题) ( 1) (2 x 1) (x 3);2 x 2 7 x 3 2 2 ( 2) (m 2n) (3n m); 6n mn m2 ( 3) (a 1) ; a 2 2a 1 ( 4) (a 3b) (a 3b); a 2 9b 2 3 2 (2 x 2 1) (x 4); ( 5) 2 x 8x x 4
练习1
( 6) (x2 2 x 3) (2 x 5) . 2 x 3 x 2 4 x 15