优课网
首页
数学
语文
英语
化学
物理
政治
历史
生物
首页
> (1)解方程:(x-3)2+4x(x-3)=0.(2)解方程:2x2-4x-7=0(3)计算:12+|3-2|+(2-π)0.(4)24-12-2(3-1).-数学
(1)解方程:(x-3)2+4x(x-3)=0.(2)解方程:2x2-4x-7=0(3)计算:12+|3-2|+(2-π)0.(4)24-12-2(3-1).-数学
题目简介
(1)解方程:(x-3)2+4x(x-3)=0.(2)解方程:2x2-4x-7=0(3)计算:12+|3-2|+(2-π)0.(4)24-12-2(3-1).-数学
题目详情
(1)解方程:(x-3)
2
+4x(x-3)=0.
(2)解方程:2x
2
-4x-7=0
(3)计算:
12
+|
3
-2|+(2-π
)
0
.
(4)
24
-
1
2
-
2
(
3
-1)
.
题型:解答题
难度:中档
来源:不详
答案
(1)把左边分解因式得:(x-3)(x-3+4x)=0,
x-3=0,x-3+4x=0,
解得:x1=3,x2=
class="stub"3
5
;
(2)a=2,b=-4,c=-7,
b2-4ac=16-4×2×(-7)=72,
x=
-b±
b
2
-4ac
2a
=
4±
72
4
=
2±3
2
2
,
x1=
2+3
2
2
,x2=
2-3
2
2
;
(3)原式=2
3
+2-
3
+1
=
3
+3;
(4)原式=2
6
×
2
2
-
6
+
2
=2
3
-
6
+
2
.
上一篇 :
下列各式计算正确的是()①26÷22
下一篇 :
You shouldn’t have quarrell
搜索答案
更多内容推荐
In order to make up for the lost time, they are working ______.A.like crazyB.as crazyC.like crazilyD
Although some people expressed their disagreement at the meeting, most of them were _____ the reform
当x______时,分式10x7+x有意义.当x______时,分式x2-16x-4的值为零.如果(a-1)0=1,则a的取值范围为______.-数学
— I’m looking for a nearby place for my holiday. Any good ideas?— How about the Moon Lake? It is ___
计算:4+(2010-3)0-(12)-1=______.-数学
计算(1)14×16-19×3-0+(3-2)0(2)(6-215)×3-612.-数学
若(a-2)a2-4=1,则a=______.-数学
_________, the subject belongs to biology.A.Strictly spokenB.Spoken strictlyC.Strictly speakingD.Sp
The big building _____ construction will be a shopping mall in the city.A.inB.underC.overD.during-高一
She's aiming ________ a scholarship. That is why she has been focusing her mind ________ her wo
Jane helped me with my work last week when I asked for leave. ______, I’ll invite her to have dinner
The market competition is fierce, but our products have great advantage ______ quality and price.A.i
---I think the company may not offer you a good pay.---_______, I won’t take the job.A.That is to sa
计算题:(1)|-2|-(1+2)0+4;(2)16+3-8-(3)2.-数学
His report was so exciting that it was interrupted by applause(鼓掌).A.constantlyB.constantC.seldomD.n
— What's he?— He works _____ an English teacher in that college. [ ]A. with B. asC. to be D. li
|-2|+(12)-1×(π-2)0-4+(-12).-数学
Tom was over there. His red clothes stood out clearly _____the snow.A.behindB.forC.against D.beyond-
When we got there, he was about to leave. So he only had time to explain _______ to us how he ______
—Hi, I hear you’re going to London this summer vacation. —, I was going to, but now I have changed m
After ten years abroad, he still recognized his old colleagues ________ he set foot in China.A.immed
33-2-(7+3)0+(-1)100•(-0.25)-2.-数学
(1)已知:4x2=81,求x.(2)计算:3-8-(1+2)0+4.-数学
–Why did you choose Jennifer as the leader of the team?--No one was equal ______ her ______ skills a
I recognized the man __________ he was shown into the room.A.at onceB.suddenlyC.immediatelyD.quickly
According to the weather report, the temperature tomorrow will rise up ______32 degrees centigrade,
计算:8-42+(12)-1=______.-数学
计算:(1)2-1-3(-8)3+(2)2;(2)(-2)2+|1-2|-(2)0.-数学
化简:(1)62-18-(12)0;(2)a+1a-1•a2-1a+1-1.-数学
It is most _____ that the environmentalists will come to the area to investigate the possible damage
He didn’t do well _____ Chinese. He had some trouble ______ it.A.in, inB.for, withC.with, forD.in, w
On the other hand, the influence______ eating habits on people’s emotions was also neglected most of
计算:(1)|-2|-9+(13)-1+(-1)2011-(π-3)0(2)xx-y+yy-x(3)(2ab2c-3)-2÷(a-2b)3(4)x-2x2-1÷x+1x2+2x+1.-数学
The headmaster asked the boy to apologize ______ the teacher _______ what he had done, but he refuse
You can chang your job, you can move house ,but friendship is meant to belife.A. ofB.onC. toD. For-高
My life has been blessed with many important occasions and achievements ________ I am proud.[ ]A. of
Tell me _______how it came about that you were 20 minutes late for class. You needn’t go into detail
Of the two coats, I’d choose the red one, for I am ______ fond of it.A.familiarlyB.speciallyC.simila
—Do you live __________ near Jim?—No, he lives in another part of the town .A.somewhere B.nowhere C
9的算术平方根为______;3-2的算术平方根是______.-数学
Tom _____ his father _____ character and some everyday habits. [ ]A. differs in; from B. differs fro
计算:|tan45°|+12-(π+2013)0+(-12)-2.-数学
—The fellow has been suspected________an email fraud.—Nowadays cybercrime is developing________
My uncle's house in the downtown area is much smaller than ours, but it is twice _____ expensiv
They traveled ________, all the way up to Wisconsin .A.the northB.in the northC.northD.the south-高三
(1)计算:2cos60°-0+9;(2)解方程:2-xx-3+3=23-x.-数学
More and more high-rise buildings have been built in big cities________ space.A.in search ofB.in pla
What a wonder! They have finished _______ half of the project in such a short time.A.no more thanB.
Could I speak to the person who is ______ International Sales, please?A.in charge ofB.in the charge
Harry, you can’t go out since you haven’t finished your homework; ______, there is going to be a he
返回顶部
题目简介
(1)解方程:(x-3)2+4x(x-3)=0.(2)解方程:2x2-4x-7=0(3)计算:12+|3-2|+(2-π)0.(4)24-12-2(3-1).-数学
题目详情
(2)解方程:2x2-4x-7=0
(3)计算:
(4)
答案
x-3=0,x-3+4x=0,
解得:x1=3,x2=
(2)a=2,b=-4,c=-7,
b2-4ac=16-4×2×(-7)=72,
x=
x1=
(3)原式=2
=
(4)原式=2
=2