题目内容
A.3a2·2a3=5a5 B.2a2·3a2=6a2
C.3a3·4b3=12a3b3 D.3a3·4a4=12a12
(1)-x2+0.04;
(2)16a2b4-8ab3c2+b2c4;
(3);
(4)y(x-y)-x2;
(5)16x5-49xy4;
(6)7am+1-14am+7am-1;
(7)(3a2-b2)2-(a2-3b2)2;
(8)2(x2+y2)(x+y)2-(x2-y2)2.
A.-3ab B.-ab
C.3a2 D.9a2
下列计算正确的是( )
A.2x+3y=5xy B.-2ba2+a2b=-a2b
C.2a2+2a3=2a5 D.4a2-3a2=1