Write it out, okay? Let x be a and y be b, then the original formula is (a-b)-ab.

a-b-ab

Are you sure it's formula method rather than factorization? Questioning factorization, formula method is more about questioning discriminant, finding root formula, formula method, how to use the blue star at the beginning, endless rotation, magnificent sea and white waves; A trickle flows through fields, villages and towns.

These are all manifestations of vitality.

(Excerpted from Hebei examinee "Life in Your Hands") The wind chimes of youth opened my heart, the colored flutes of youth blew my dreams, and the notes of youth drove me to hope.

Youth, this beautiful season, is the time for us to sow hope. Cherish it, grasp it and let it shine in our hands. It is said that the ship of life is inseparable from the ideal sail.

It is said that the ideal of life is for the ideal life.

The happiest time in an ideal life is the flower season of dreams.

Love is a ray of sunshine in winter, which dispels the cold frost. Love is a shower after a long drought, nourishing a broken heart; Love is a beacon in Wang Yang, which indicates the hope of a new life.

(Excerpted from Jingzhou Examiner's Bringing Love to Others) I wonder if I passed by. You are like a cloud on the horizon. Even if you can't satisfy it, you have taken away my attention ... (from Guangdong examinee's "I pay attention to the dribs and drabs of life") In life, everyone will encounter unsatisfactory things, such as setbacks, misunderstandings, criticisms and so on.

The feeling at that time was undoubtedly an insurmountable obstacle.

But then suddenly looking back, it was just a wave in the long river of life, a wisp of fragrance of colorful years.

(Excerpted from Chongqing examinee Xiangxiang) Life needs applause.

Many people often lament that educated youth is hard to find.

What is a bosom friend? Isn't the applause of life a confidant? (Excerpted from Anhui examinee "Life Needs Applause") Just as wind is to sails, just like temperature is to seeds, just like sunshine and rain are to the growth of all things, praise is an indispensable spiritual nutrition in our growth process.

(Excerpt from Anhui examinee praise desire) There is a kind of flower in the world that will never fade, and that is a smile.

It is open all year round, north and south, as long as there are crowds.

The nobler the thought, the more beautiful the flower of smile.

At the end of the article, life is a burning flame, and it will shine in the ashes, because life is in your hands, so you just have to grasp it well.

(Excerpted from Hebei examinee "Life in Your Hands") What is youth? Youth is hope.

What does youth need? Youth needs to be grasped.

Youth without regrets, perfect answer sheet, grasp it well.

When the spring breeze blows out, looking back, grasping carefully and doing everything well, at least "this" is also a confession of our life.

Hold your youth in your hands, keep your hopes in your heart, pursue with your hopes and dreams, struggle and create the brilliance of your youth.

(Excerpted from Hebei students' Grasping Youth) In the flower season, I hope to always remember the good words of the sages: the ship of life cannot be separated from the ideal sail.

The ideal of life is for the ideal life.

(Excerpted from Jingzhou examinee's "Bringing Dreams to the Flower Season") Let's take action and bring love to those children who are out of school, to those lonely old people … to everyone around us.

When you give your love to others, you also get great happiness.

I believe that as long as everyone gives a love, the world will become a beautiful world.

(Excerpted from Jingzhou examinee "Bringing Love to Others") Attention need not be melodramatic, but it will only be unintentional. That seriousness and persistence, like a butterfly flying to the sky, took away my attention and inadvertently brought news of life and love to life! (Excerpted from Guangdong examinee "I pay attention to the dribs and drabs of life") Every time I think about it, my heart is sour, but this grievance has not sublimated into hatred, but it has created my strong character, and I also understand the teacher's mood.

If it weren't for that time, would I feel wronged? Ha ha! There is no trace of time, only fragrance.

(Excerpted from Chongqing examinee Xiangxiang) The applause of life will never stop? It always inspires people to pursue the nobleness and perfection of the soul. Applause is more important than love and money.

Let applause ring, life needs applause.

Dear teachers, how eager to get your praise, even if it is a simple sentence or two! (Excerpted from Anhui examinee's Desire for Praise) Bring a smile to life and decorate life with a smile.

You don't have to look for happiness and beg for time's mercy, but walk through the four seasons with a smile, then store it as happy wine and enjoy life.

(Excerpted from Jingzhou examinee's "Bringing Smile to Life") A highly summarized, meaningful and intriguing sentence.

Taste the past, bitter with sweet, spray after spray, fragrance after fragrance like an eternal flame, lit my lamp of hope, so I saw the road clearly and moved on.

(Excerpted from Chongqing examinee "A wisp of incense") There are dances in ordinary life and songs in trivial things.

Success is an enterprising melody plucked from the heartstrings, and success is a calm emotional lake thrown into a series of armchairs by a little progress.

What's wrong with savoring your tiny success and not being applauded? Excerpted from Anhui examinee "Applause for Yourself") Praise is to ignite the fire in others' hearts with your own heart, find others' hearts with your own heart, and moisten things with spring breeze and drizzle.

(Excerpted from Anhui examinee's "Desire for Praise") In winter, there is no prosperity in spring, publicity in summer and richness in autumn, but she has the qualities of holiness, fortitude and selflessness.

(Excerpted from Zibo examinee's Winter Personality) Yes, love blows away the shadow of life and sows brilliant sunshine.

If happiness is fire, love is burning, happiness is water and love is flowing.

Love and happiness go hand in hand! (Excerpted from Jingzhou examinee "Bringing Love to Others") Innovation is to bid farewell to the past, grasp the present and welcome the future.

How about (from Chongqing examinee "Cool")? A lot of trouble.

But I always believe that no matter how cloudy the weather is, it will be fine.

(Excerpted from Linyi examinee's Growing Pains) So I rearranged my old bags, propped up the dust on my body, replaced the illusion of the past with dignity, and left a deep impression under my feet with firmness.

Go forward bravely, face forward, meet the glory of life without regrets, and create the fiery red of life.

(Excerpted from Henan examinee "When I Face North Korea" ...

How to write 1 of several square difference formulas? Calculate the square of: 18 1 Original formula = (181-61) * (1865438). (301181) =120 * 242/120 * 482, you will know later; What are you going to do with the remaining three questions, factorization? 2. = [4 (xy)-5 (x-y)] * [4 (xy) 5 (x-y)] = (-x9y) * (9x-y), which should be known later; This seems to have nothing to do with the variance of peace. Are you wrong? If the quadratic cube is replaced by the quadratic cube, it can be calculated as: = 3 [(AB) 2-9 * C2] = 3 [(AB)-3C] [(AB) 3C], if it is correct, then I won't; 4.=x^2 6 * 8 x^2-4=2*x^2 6 * 4 = 2(x 1)(x ^ 2)。

Formula method of mathematics problems in grade three, quadratic equation of one variable. Speed up, please.

My view on the quadratic equation of one yuan Both the quadratic equation of one yuan and the linear equation of one yuan are integral equations, which are a key content of junior high school mathematics and the basis for students to learn mathematics in the future.

Before talking about the solution of a quadratic equation, explain the difference between it and a quadratic equation.

According to the definition, an integral equation with only one unknown and the highest degree of the unknown is 2 is called a quadratic equation with one variable, and the general formula is:

The quadratic equation with one variable has three characteristics: (1) contains only one unknown; (2) The maximum number of unknowns is 2; (3) is an integral equation.

Therefore, to judge whether an equation is an unary quadratic equation, we must first look at whether it is an integral equation. If so, then tidy it up. If it can be arranged in a form, then this equation is a quadratic equation.

Let's talk about the solution of a quadratic equation.

The basic thinking method of solving a quadratic equation with one variable is to simplify it into two quadratic equations with one variable.

There are four basic solutions to the quadratic equation of one variable: 1, direct Kaiping method; 2. Matching method; 3. Formula method; 4. Factorial decomposition method.

Table below: The method is applicable to equation types. Note: There is a solution when the direct leveling method is ≥0. If the coefficient of the quadratic term of the matching method is not 1, the coefficient must be changed to 1 before making the formula.

When the formula method is ≥0, the equation has a solution; One side of the factorization equation is 0, and the other side is decomposed into the product of two linear factors.

One side of the equation must be 0, and the other side can be decomposed in any way.

Example analysis example 1: known, solving the equation is about.

Analysis: Pay attention to what kind of equation the satisfied value will make the original equation become.

Solution: you get: or, at that time, the original equation was, solved. At that time, the original equation was, was solved. Note: From this problem, we can see that only when the term coefficient is not 0, and it is the highest term, the equation is a quadratic equation with one variable, and it can be solved by the quadratic equation with one variable. The description of the quadratic equation in one variable in the problem is incomplete, so it is the highest secondary explanation.

Generally, the unary quadratic equation described in general form is more concise, that is, the equation in shape is called the unary quadratic equation about.

If there is no condition for this question, it is necessary to discuss the letter coefficient of the item after sorting it out.

Example 2: Solving the following unary quadratic equation by Kaiping method.

( 1); (2) (3); (4) Analysis: The direct Kaiping method is a method to solve the direct square root of a quadratic equation.

The direct Kaiping method is used to solve the equation of form, and its solution is.

Through observation, it is not difficult to find that the equations in (1) and (2) are obviously easy to be solved by direct Kaiping method; (3) The equation can be completely flat on the left and121> on the right; 0, so this equation can also be solved by direct Kaiping method; The fourth sub-question, the left side of the equation can be solved by square difference formula, and then the constant can be moved to the right side, so it can be solved by direct Kaiping method.

Solution: (1) ∴ (Be careful not to lose the solution) The solution of the original equation is:, (2) The solution of the original equation is:, (3) ∴, ∴.

To solve the equation directly by Kaiping method, it should be noted that when both sides of the equation have roots at the same time, just take the symbol of one side, and be careful not to lose the solution.

Example 3: Solve the following quadratic equation with one variable by matching method.

( 1); (2) Analysis: To solve the equation by collocation method, we must first move the constant to the right of the equation, and then transform the quadratic coefficient into 1, which becomes the form of.

The problem (1) can be reduced to, and then the square of half the coefficient of the first term is added to both sides of the equation at the same time, that is, the left side of the equation constitutes a completely flat road, and the right side is a constant not less than 0, that is, it can be solved by direct Kaiping method.

Question (2) In the formula, special attention should be paid to adding the square of half the coefficient of the first term to both sides of the equation at the same time.

Solution: (1) Convert the quadratic term into 1, move the constant term to:, and the formula is:, that is, the square root is directly: ∴, ∴ The solution of the original equation is:, (2) Convert the quadratic term into 1, and move the constant term to: both sides of the equation.

The formula should be made according to the following steps: firstly, the quadratic term coefficient is changed to 1, and the constant term is moved to one side; Then add the square of half the coefficient of the first term to both sides of the equation at the same time.

Finally, the problem-solving task can be completed by using the direct Kaiping method.

Example 4: Solve the following equations by formula method.

( 1); (2) Analysis: To use the formula method is to use the root formula. When it is used, the quadratic equation of one variable is first transformed into a general form, and then the value of the discriminant is calculated. When ≥0, the root of the equation can be obtained by substituting the values of various coefficients into the formula for finding the root.

However, it should be noted that when 0 is substituted into the root formula:, ∴, (2) is converted into the general formula: find the value of discriminant: >; 0 ∴ ∴, explanation: Formula method can be used to solve any quadratic equation with one variable. When a simple method cannot be found, the formula method is regarded as a general form and then used.

However, in application, we must first make clear the quantity expressed by letters in the formula, then find out the value of the discriminant and simplify the root of the solution.

Example 5: Solve the following equations by factorization.

( 1); (2) Analysis: Factorization is to convert the equation into a form with one side zero, and decompose the quadratic trinomial on the other side into the product of two linear factors, so that the two linear factors are equal to zero respectively, and two linear equations are obtained. The roots obtained by solving these two linear equations are the two roots of the original equation.

The problem (1) is already a general formula and can directly decompose the factors on the left; Problem (2) must be simplified to a general formula before factorization.

Solution: (1) The left side is decomposed into the product of two factors, so you can get:, ∴, (2) Simplify into a general formula: The left side is decomposed into the product of two factors, so you can get:, ∴, which shows that when using factorization, one side of the equation must be simplified to 0, so as to achieve the purpose of order reduction.

The method of turning one side of the equation into 0 and factorizing the other side can be used to solve various equations encountered in the future.

Because this is one of the important means to simplify the equation.

From the above example, the basic idea of solving a quadratic equation is to solve a quadratic equation. ...

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Please indicate the source? (x-y)-xy is calculated by the formula.