1.4 整式的乘法,第1课时 单项式与单项式相乘,5.计算: ( 1 )( -4xy3 )( -2x ); 解:原式=8x2y3. ( 2 )( -2.4x2y3 )( -0.5x4 ). 解:原式=1.2x6y3.,6.下列运算正确的是 ( D ) A.( -2ab )( -3ab )3=-54a4b4 B.5x2( 3x3 )2=15x12 C.( -0.1b )( -10b2 )3=-b7,7.( 青岛中考 )计算( a2 )3-5a3a3的结果是 ( C ) A.a5-5a6 B.a6-5a9 C.-4a6 D.4a6 8.计算( 2m2n-2 )23m-2n3的结果是 . 9.已知A=3x2,B=-2xy2,C=-x2y2,则AB2C= -12x6y6 .,10.计算: ( 1 )( 2x2y )( 3xy2 )-4xy( xy )2; 解:原式=6x3y3-4x3y3=2x3y3.,12.已知x3m=2,y2m=3,求( x2m )3+( ym )6-( x2y )3mym的值. 解:x3m=2,y2m=3, ( x2m )3+( ym )6-( x2y )3mym =( x3m )2+( y2m )3-( x6my4m ) =( x3m )2+( y2m )3-( x3my2m )2 =22+33-( 23 )2=-5.,
