优课网
首页
数学
语文
英语
化学
物理
政治
历史
生物
首页
> (1)化简:45+1220-515(2)先化简,再求值:aa+3-3a-9a2-9,其中a=1.-数学
(1)化简:45+1220-515(2)先化简,再求值:aa+3-3a-9a2-9,其中a=1.-数学
题目简介
(1)化简:45+1220-515(2)先化简,再求值:aa+3-3a-9a2-9,其中a=1.-数学
题目详情
(1)化简:
45
+
1
2
20
-5
1
5
(2)先化简,再求值:
a
a+3
-
3a-9
a
2
-9
,其中a=1.
题型:解答题
难度:中档
来源:不详
答案
(1)原式=
9×5
+
class="stub"1
2
4×5
-5
class="stub"5
5×5
,
=3
5
+
class="stub"1
2
×2
5
-5×
class="stub"1
5
5
,
=
3
5
+
5
-
5
,
=
3
5
;
(2)原式=
class="stub"a
a+3
-
3(a-3)
(a+3)(a-3)
,
=
class="stub"a
a+3
-
class="stub"3
a+3
,
=
class="stub"a-3
a+3
,
当a=1时,原式=-
class="stub"1
2
.
上一篇 :
(3xx-2-xx+2)×x2-4x.-数学
下一篇 :
(xy-x2)÷x2-2xy+y2xy•x-yx2-
搜索答案
更多内容推荐
先化简,再求值:2xx-3+x3-x,其中x=-1.-数学
先化简,再求值:(1+x-3x+3)÷2xx2-9,其中x=4.-数学
_______ never to come back, the boy left his home angrily.A.DeterminedB.DeterminingC.Being determin
先化简:(1+3a-2)÷a+1a2-4,然后请你给a选取一个合适的值,再求此时原式的值.-数学
化简分式:(2a-1-1a+1)÷1a2-1,并从-2,-1,0,1,2中选一个能使分式有意义的数代入求值.-数学
将下面的代数式化简,再选择你喜欢且有意义的数代入求值.(1a-b+1a+b)÷aba2-b2+a-1.-数学
计算(1-11-a)(1a2-1)的结果为()A.-a+1aB.a-1aC.a1-aD.a+11-a-数学
先化简,再求值:①2x+1-1x2-1÷xx2-2x+1,其中x=5;②(x-1x-x-2x+1)÷2x2-xx2+2x+1,其中x满足x2-x-1=0.-数学
______ from heart disease for years, Andy has to take some medicine with her wherever she goes. A.T
The tower_____ in the 1800s is the oldest building in this area.A.to be completedB.being completedC
If the building project_______ by the end of this month is delayed, the construction company will be
先化简再求值:3ab-a3b+a2b2a2+2ab+b2÷a2-aba2-b2,其中:a=5+1,b=5-1.-数学
先化简再求值:1x-1-1x2-x,其中x=2.-数学
先化简再求值:4aa2-4-2a-2,其中a=2-2-数学
先化简,再求值:2xx2-4x-1x-2,其中x=-3.-数学
_____ his electronic dictionary made himself sad.A.LosingB.LostC.Being lostD.To be lost-高二英语
They are broading the bridge to _____the flow of traffic.A.put offB.speed upC.turn onD.work out-高三英语
---Did you enjoy yourself at the party? ---Yes.I appreciated_________.A.to be invitedB.to have invit
先化简,再求值:(1a-b+1b+a)÷aba+b,其中a=2+1,b=2.-数学
计算(1)(ab)-10(-a4b3)-3•a-2b(2)a-ba-c÷(b-ab-c÷c-ac-b(3)当x=2时,求x2-1x2+x-2÷(1+1x2+2x)的值.-数学
____inherskirt,thelittlegirltriedtomakeherself_____attheparty.A.Dressed;noticeB.Dressing;noticedC.Dr
______ hard all day, I fell fast asleep. A.WorkingB.Having worked C.WorkedD.To work-高二英语
Every evening after dinner, if not ______from work, I will spend some time _____ my dog.A.tired; wa
先化简:(x2-2x+1x2-1+1x)÷1x+1,再取一个你认为合理的x值,代入求原式的值.-数学
化简求值:(1)4x2-8xy+4y22x2-2y2,其中x=2,y=3;(2)(a-b+4aba-b)(a+b-4aba+b),其中a=32,b=-12.-数学
已知x=2010,y=2009,求代数式(x-2xy-y2x)÷x-yx的值.-数学
Not recognizing me at first, __________.A.he closed the doorB.the door was closedC.the door was clos
There are many tall old trees____ in and around our school.A.stoodB.to standC.standingD.being standi
I regretted _________ a lecture made by proffessor. Wu.A.missingB.toC.missD.missed-高二英语
She soon _________ French when she went to live in France.A.set upB.took upC.put upD.picked up-高三英语
Mary escaped __________ for her coming late for school this morning.A.from punishmentB.punishingC.be
计算(a2+b2a2-b2-a-ba+b)×a-b2ab的结果是()A.1a-bB.1a+bC.a-bD.a+b-数学
In the 28th summer Olympic Games , America won the most gold medals ,first .A.rank B.ranki
You should pay more in Beijing if you want to rent an apartment ___________ south.A.facingB.faceC.fa
化简:x3•(1x3-1x2+1x)-数学
1-x-yx+2y÷x2-y2x2+4xy+4y2.-数学
Since you have had your cell phone _____ , you don’t need to borrow mine. A.repairing B.to repair C
先化简,再求值:(1+1m-2)÷m2-12m-4,其中m=-5.-数学
______ me the truth, or I’m not going to leave the room.A.TellB.TellingC.To tellD.If you tell-高一英语
计算:(1)a-bab+b-cbc+c-aac;(2)ba-b+b3a3-2a2b+ab2÷ab+b2b2-a2.-数学
先化简,再求值:1a+1-a+1a2-2a+1÷a+1a-1,其中a=2.-数学
已知a=3,b=-2,求(1a+1b)•aba2+2ab+b2的值.-数学
______ the same story many times, my little brother can now tell it himself.A.TellingB.Having toldC.
— Can I help you?— Yes, I’m looking for a pen.— We have some new arrivals for you to ______A.selectB
先化简、再求值:x2+y2x-y+2xyy-x,其中x=3+2,y=3-2.-数学
先化简,再求值:(2a+1a2-1+11-a)÷a,其中a=2.-数学
Every minute is made full _______ of _______ our lessons well.A.to use; studyB.use; studyingC.use; t
The play ______ next month aims at mainly to reflect the local culture.A.producedB.being producedC.t
It seemed that the boy who you _____ didn’t show any interest in what he was reading at all.A.were m
先化简-2xyx2-y2÷(1x-y-1x+y),再求值,其中x=1-2.-数学
返回顶部
题目简介
(1)化简:45+1220-515(2)先化简,再求值:aa+3-3a-9a2-9,其中a=1.-数学
题目详情
(2)先化简,再求值:
答案
=3
=3
=3
(2)原式=
=
=
当a=1时,原式=-