问题
解答题
2b
|
答案
①当a>0,b>0时;
原式=2b×
+ab b
×a3 a
-(4a×ab
+3ab a
)ab
=2
+3ab
-4ab
-3ab ab
=-2
.ab
②当a<0,b<0时,
原式=2b×(-
)+ab b
×(-a3 a
)-[4a×(-ab
)+3ab a
]ab
=-2
-3ab
+4ab
-3ab ab
=-4
.ab
2b
|
①当a>0,b>0时;
原式=2b×
+ab b
×a3 a
-(4a×ab
+3ab a
)ab
=2
+3ab
-4ab
-3ab ab
=-2
.ab
②当a<0,b<0时,
原式=2b×(-
)+ab b
×(-a3 a
)-[4a×(-ab
)+3ab a
]ab
=-2
-3ab
+4ab
-3ab ab
=-4
.ab