What does 4A2B mean b2 What does 4ac mean?

4A2B can go to the four famous schools in Changsha.

The results of the high school entrance examination in Changsha urban area were announced, and the minimum control line for the admission of index students was delineated.

If you have any doubts about the test results, please submit an application to the school before 5:30 p.m. on the 6th.

This newspaper reported on July 3.

According to the news from the Changsha Municipal Education Bureau, the 2009 urban high school examination papers, unified scores, score transfers, and ranking conversion were all completed today, and the results of the high school entrance examination were announced in the early morning of July 4. This year, there are 21,060 junior high school graduates in Changsha City, and a total of 20,918 people are referenced in addition to 142 direct promotion students.

The reporter learned today from the Changsha Municipal Education Bureau that the minimum control line for the admission of index students in the city was demarcated today (see **).

The recruitment office of the city's education bureau requires schools to seriously organize and guide students to fill in the index student volunteers. The school should publicize the index student plan in the school to ensure that each candidate understands the relevant policies; Students must be within the stipulated time (deadline: July 4 at 5 p.m

30) Submit the "2009 Changsha Urban Index Student Voluntary Filling Form" to the school. Students who have the qualifications of index students and want to enter the corresponding school of index students, please be sure to fill in the index student volunteer; If you do not fill in the index student volunteer of the corresponding school, and fill in the school volunteer online as a general candidate, you cannot be admitted to the school.

According to the recruitment office of the city's education bureau, the graduating schools will determine the candidates for the index students in the following order according to the number of indicators and the students' volunteers: Compare academic performance rankings; Compare the comprehensive quality assessment rankings; Compare the preferential policies in order; Compare the overall ranking combinations of Chinese, Mathematics and English in the written examination; Compare the rankings of the three subjects of Chinese, Mathematics and English in order of academic examination; The total results of the five final examinations of Chinese, mathematics and English in the three years of junior high school were compared.

The city's Education Bureau requires that schools should notify each candidate of the precautions for online volunteer filling, and it is strictly forbidden to keep the student handbook for junior high school graduates, and it is strictly forbidden to fill in or change student preferences on behalf of students. For students who are admitted as index students, the application filled in online is invalid.

Schools should open computer rooms to provide conditions for students to fill in their online volunteers, but they must not require students to fill in the application on campus.

Enrollment at the high school level will be divided into batches according to their wishes, and each batch will admit government-funded students first, and then admit students who choose to choose schools. Candidates can choose to fill in four batches of volunteers.

This year, the provincial demonstration ordinary high school will be admitted in two batches, and the admission order is:

The High School Affiliated to Normal University, No. 1 Middle School, Changjun Middle School (including Changjun Bilingual), Yali Middle School, Mingde Middle School, Zhounan Middle School, Tin Ka Ping Experimental Middle School, Lei Feng School.

Other provincial exemplary ordinary high schools.

Reporter Wang Wenlong.

The results of the high school entrance examination in Changsha City were announced.

You can log on to the Changsha Education Information Network for inquiries.

It should be the school cut-off score. and fractional grades.

=b2-4ac is the judgmentUnary quadratic equationsThe formula for the number of real roots.

There is only one unknown number (unary), and the highest number of unknowns is an integer of 2 (quadratic).

The equation is called a quadratic equation [1]. The unary quadratic equation can be formed into a general form ax+bx+c=0(a≠0). where ax is called the quadratic term, and a is the quadratic coefficient; bx is called the primary term, and b is the coefficient of the primary term; c is called a constant term.

For a quadratic equation to be true, three conditions must be met at the same time:

1. It is an integer equation, that is, both sides of the equal sign are integers, and if there is a denominator in the equation; And the unknown number is on the denominator, then this equation is a fractional equation.

It is not a quadratic equation, if there is a root number in the equation and the unknown number is in the root number, then the equation is not a quadratic equation (it is an irrational equation).

2. Contains only one unknown.

3. The maximum number of unknown items is 2.

International System of Units, the unit of current is a, and the current in the conductor is 2a.

The V and A in 5V 2A represent the maximum output voltage and current of the charger, 5V 2A means that this charger can input 5 volts of voltage, 2 amps of current, all mobile phone chargers are actually composed of a stable power supply (mainly a stabilized power supply, providing stable working voltage and sufficient current) plus the necessary constant current, voltage limiting, time limit, overshoot and other control stool Ling Road.

The output parameters marked on the original charger (finger charger): for example, the output output is the relevant parameters of the internal regulated power supply. For example, the output can be used for devices, and it can be used for 6V devices. When charging, you can choose the appropriate accessories according to the parameters on the charger.

Electric currents are classified as alternating currents.

Current and direct current.

Flow. 1. Alternating current: The magnitude and direction change periodically. In life, plug-in wall appliances use civil AC power supply.

2. Direct current: the direction does not change with time. The removable external power supply used in daily life provides direct current.

Alternating current is widely used in family life and industrial production, and the domestic voltage is 220V and the general industrial voltage is 380V, which are all dangerous voltages.

Direct current is widely used in flashlights (dry batteries.

Mobile phones (lithium batteries) and other small household appliances, etc.

This is the root finding formula for a quadratic equation, first reducing the quadratic equation to the standard form: ax +bx+c=0(a≠0), and then judging =b -4ac.

In this set of formulas, the former formula is used to find the real roots when the discriminant formula of the equation is not negative, and the latter formula is used to find the two conjugate imaginary roots when the discriminant formula of the equation is negative.

When the equation is a quadratic equation with rational coefficients and requires a rational number root, it can only be solved if δ=b2-4ac is a perfectly squared number of a rational number.

2a2b is a term for a guess the number game and is often used to describe the outcome of guessing a number. Among them, 2 means that you guessed the number and position correctly, and A means that you have a number that guessed the correct position. The following 2 means that the number is correct, but the position is wrong, and B means that there are b numbers that have been guessed correctly, but the position is wrong.

In general, the sum of a and b indicates the number of numbers that are guessed correctly. For example, let's say the answer is 1234 and you guess the number is 1325. Then there are 2 numbers to guess the correct position, i.e. 1 and 3, so the beat is closed a=2;There are 2 who guess the number correctly but in the wrong position, i.e. 2 and 5, so b=2.

So, the answer here is 2a2b. With such descriptions, the game of guessing numbers can give a more specific guess and help the player gradually approach the correct answer.

This means that 4 subjects are excellent and 3 subjects are good. For example, 5 A's mean excellent in 5 subjects, excellent in 4 A's, and good results in 1 subject. A+ is perfect, 95-100 points B+ is good, 85-90 points, A is excellent, B is good, C is pass, D is unqualified.

On a 100-point scale, 100-90 is A, 90-70 is B, and less than 70 is C.

The high school entrance examination adopts a 100-point system for Hong's to mark the papers, and the grades and stars present the results. The maximum score in the junior high school academic examination for the missing subjects such as Chinese, Mathematics, English, Physics, Chemistry, Politics and History is 110 points each.

The subject grade is determined by the original score of the academic examination and is presented as ten grades and two stars. The full score of the physical education test is 30 points, and the physical education subject grade is presented as 3 levels according to the original score. The ten levels of Chinese, Mathematics, English, Physics, Chemistry, Politics, History and other subjects are divided as follows:

A (95-100 points), B (90-94 points), C (85-89 points), D (80-84 points), E (75-79 points), F (70-74 points), G (60-69 points), H (50-59 points), I (40-49 points), J (below 39 points).