问题
解答题
先化简，再求值：（
|
答案
原式=
+3x+2 (x+1)(x-1) x(x-1) (x+1)(x-1)
=3x+2+x2-x (x+1)(x-1)
=2x+2+x2 (x+1)(x-1)
=
，(x+1)2+1 (x+1)(x-1)
∵x=（-1）2012+tan60°=1+
，3
∴原式=(1+
+1)2+13 (1+
+1)(1+3
-1)3
=(2+
)2+13 (2+
)×3 3
=4+3+4
+13 2
+33
=4(2+
)3 2
+33
=
．4 3 3