问题
选择题
已知
|
答案
∵
+1 a
=3,1 b
∴
=3,a+b ab
∴a+b=3ab,
∴原式=3ab 2(a+b)+3ab
=3ab 2×3ab+3ab
=3ab 9ab
=
.1 3
故选D.
已知
|
∵
+1 a
=3,1 b
∴
=3,a+b ab
∴a+b=3ab,
∴原式=3ab 2(a+b)+3ab
=3ab 2×3ab+3ab
=3ab 9ab
=
.1 3
故选D.