(1)观察下列等式:1(1+1×2)(1+2×2)=12(11+1×2-11+2

题型:解答题

问题:

(1)观察下列等式:
1
(1+1×2)(1+2×2)
=
1
2
(
1
1+1×2
-
1
1+2×2
)

1
(1+2×2)(1+3×2)
=
1
2
(
1
1+2×2
-
1
1+3×2
)

1
(1+3×2)(1+4×2)
=
1
2
(
1
1+3×2
-
1
1+4×2
)

根据等式的规律填空:
1
[1+2(n-1)](1+2n)
=______;
(2)利用(1)的结论先化简代数式:
1
(1+x)(1+2x)
+
1
(1+2x)(1+3x)
+
1
(1+3x)(1+4x)
+
1
(1+4x)(1+5x)
+
1
(1+5x)(1+6x)
+
1
(1+6x)(1+7x)

再求当x=
-4+
30
7
的值.
考点:分式的加减乘除混合运算及分式的化简最简二次根式
题型:解答题

毛 * * 最早提出新民主主义这一概念的著作是 ( )

A.《中国革命和中 * * 党》

B.《< * * 党人>发刊词》

C.《论联合政府》

D.《新民主主义论》

题型:解答题

If you walk through the streets of any big city at six or seven in the morning, the chances are that you will see women hurrying along, pushing prams (婴儿推车). You may see more than one woman   1  on the same door and, as it opens, quickly kiss the child,   2  a package of nappies and hurry off down the street to clock on the early shift in an office, leaving their children to a child – minder – a woman who may be doing the job legally or illegally, well or badly. Brain Jackson, director of the Child – minding Researching Unit, and his colleagues have done a great deal of work in finding out   3  it means for a child to spend the first years of life in the care of a child – minder.
  4  law, anyone who looks after a child for more than two hours a day and gets paid must be registered.  5  the punishment is a 6 pounds fine. Local authorities are responsible for the registration and supervision (监管) of minders. The regulations   6  adequate provision (保障) for fire, safety and health. Very few minders can   7  these. Yet, not many districts give financial assistance. “This means,” Brain Jackson says, “that when you have one registered minder tested and proved by the local authorities, you can be sure that you will get a dozen unregistered, illegal minders   8 .”
The researchers found themselves   9  into the role of private investigators when they conduct their   10 . Getting up early to do a “Dawn Watch” following mothers through cold, dark streets and nothing where they left their babies, Jackson says, was a long, slow process.
小题1:
A.knockB.stopC.stickD.stay
小题2:
A.hand outB.hand inC.hand downD.hand over
小题3:

2,4,6

 
A.whichB.whatC.howD.that

小题4:
A.ForB.ThroughC.ByD.With
小题5:
A.ThereforeB.HoweverC.OtherwiseD.Moreover
小题6:
A.requireB.demandC.insistD.acquire
小题7:
A.payB.offerC.affordD.do
小题8:
A.at workB.in publicC.in vain D.at present
小题9:
A.runB.lookedC.forcedD.dropped
小题10:
A.experimentB.surveyC.viewD.project
题型:解答题

不影响MAC的因素,除外()

A.麻醉时间

B.性别

C.昼夜变化

D.甲状腺功能降低

E.代谢性酸中毒

题型:解答题

利用地价资料评估基准地价的常用模型有( )。

A.指数模型

B.算数平均数模型

C.多元线性模型

D.生产函数模型

题型:解答题

西夏国唯一的太上皇是()。

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