计算 (1)(−1/2)−1−23×0.125+(3−27−2012)0 (2)(−ab)2÷(2a25b)2•a/5b (3)m+2n/n−m+n/m−n−2n/n−m (4)(x/x−y−2y/x−y)•xy/x−2y÷(1/x+1/y

问题描述:

计算
(1)(−

1
2
)−123×0.125+(
3 −27
−2012)0
(2)(
−a
b
)2÷(
2a2
5b
)2
a
5b

(3)
m+2n
n−m
+
n
m−n
2n
n−m

(4)(
x
x−y
2y
x−y
)•
xy
x−2y
÷(
1
x
+
1
y
)

(1)原式=-2+8×0.125+1=-2+1+1=0;(2)原式=a2b2÷4a425b2•a5b=a2b2•25b24a2•a5b=5a4b;(3)原式=m+2nn−m-nn−m-2nn−m=m+2n−n−2nn−m=m−nn−m=-1;(4)原式=x−2yx−y•xyx−2y÷x+yxy=x−2yx−y•xyx...