Yu jiao and Yu jiao lesson 2 teaching plan

Teaching objectives:

Knowledge and ability

Can correctly express the direction by angle, and can skillfully calculate the problems related to angle.

Process and method

Through practical operation, we can understand the application of azimuth in real life and develop abstract thinking.

Emotions, attitudes and values

Can actively participate in mathematics learning activities, cultivate students' curiosity and thirst for knowledge about mathematics.

Teaching emphasis: the representation of orientation.

Teaching difficulty: accurate representation of orientation.

Teaching preparation: preview the relevant contents in the book.

Preview and guidance:

As shown in the picture, please tell me where the four rays represent.

Teaching process;

First, create a scene and talk about it.

In real life, there is an angle that is often used in aviation and navigation. In surveying and mapping, navigators often use maps and compasses to measure this angle. This is azimuth, which is widely used. What is azimuth?

Second, speak carefully, pull away, question and ask difficult questions.

Azimuth is actually an angle indicating direction. This angle describes the direction of objects based on true north and true south, such as "30 northeast" and "40 southwest". Orientation cannot be based on due east and due west, such as "60 in the northeast and 50 in the south west", but it can sometimes be described as northeast, such as 45 in the northeast.

Third, classroom activities, intensive training

Example 1 As shown in the figure, point out the direction indicated by rays OA and OB in the figure.

(Students answer individually, students comment)

If the lighthouse is located 30 east of the north of the ship, where is the ship in the lighthouse?

(Group discussion, individual answer, teacher's summary)

As shown in Figure 3, during the voyage of cargo ship O, lighthouse A was found in the directions of 60 east by south, 60 east by north, and west by south 10, and passenger ship B, cargo ship C and island D were found in the northwest respectively. According to the method of indicating the direction of the tower, rays representing the directions of passenger ship B, cargo ship C and island D were drawn.

(Teacher's analysis, a student goes to the blackboard, and the student comments)

Fourth, extend and expand and consolidate internalization.

Example 4 A sentry measured the position of a ship at 8 a.m. at 30 southwest of the post 10, and at 10 a.m. at 60 northeast of the post, 8 km away from the post.

(1) Please draw according to the ratio of 1: 200000.

(done independently, a student walks to the blackboard and the student comments)

(2) Determine the sailing direction and progress of the ship through measurement and calculation.

(Group discussion, draw a conclusion, and the representative speaks)

Five, homework, classroom feedback

Exercise: Please draw the positions of the following points with protractor and scale.

(1) Point A is 30 northeast of point O, and the distance from point O is 3cm.

(2) Point B is 60 southwest of Point O and 4cm away from Point O..

(3) Point C is in the northwest of Point O and in the north of Point B..

Homework: Book P1407,9

Mathematics teaching plan of the first volume of the second day of junior high school

Equality and equation teaching plan

Teaching objectives

1, students master the definition of equation and the difference between equation and equation;

2. Make students master the definition of the solution of the equation and know whether a certain value is the solution of the specified equation.

Teaching focus

The method of testing the solution of equation

Teaching difficulties

Distinguish between equality and equality; Equality and identity; Identities and equations.

overall arrangement

Equation and its solution

I. Equality and identity:

Second, the equation and integral equation:

Third, the solution of the equation and the root of the equation:

Teaching design

First, review the introduction:

(1) Guess age:

Multiply your age by 2 and subtract 5. What's your score? If it is 2 1, I can guess your age is 13.

(2) Find a pattern:

If Xiao Ming's age is X, then multiplying by 2 minus 5 is 2x-5, and the equation (equation) is obtained: 2x-5 = 2 1.

Second, the new teaching:

1. Equality and identity:

① Equation:

Such as 1+2=3, 5.3-(- 1.2)=6.5, x+2x=3x, x+3=5. , called the equation.

The formula on the left of the equation is called the left of the equation;

The formula on the right side of the equation is called the right side of the equation;

The general form of the equation is: a = b.

② Identity:

1+2=3, 5.3-(- 1.2)=6.5, x+2x=3x, a+b=b+a and other equations are called identities.

2. Equations and integral equations:

① Equation:

This equation with unknowns is called equation.

② Integral equation:

When both sides of an equation are algebraic expressions, it is called an integral equation.

Exercise: After class 1 and 2 questions (assign students to answer orally).

Solutions and roots of 1. equation;

The solution of (1) equation:

The value of the unknown that can make the left and right sides of the equation equal is called the solution of the equation;

(2) the unary equation:

An equation with only one unknown number is called a unary equation;

The solution of the unary equation is also called the root of the equation.

2. One-dimensional linear equation:

An integral equation with only one unknown number and the unknown number is 1 is called a linear equation with one variable.

Check whether the following numbers are the solutions of the equation 7x+ 1= 10-2x:

⑴x = 1； ⑵x=-2 .

Solution: (1) Substitute x= 1 into the left and right sides of the equation, and get

Left =7 1+ 1=8,

Right = 10-2 1=8,

∫ Left = right,

X= 1 is the solution of equation 7x+ 1= 10-2x.

(2) Substitute x=-2 into the left and right sides of the equation, and get

Left =7(-2)+ 1=- 13，

Right = 10-2(-2)= 14,

Around ∵,

X=-2 is not the solution of equation 7x+ 1= 10-2x.

Third, homework:

homework

Synchronous practice

Mathematics teaching plan of the first volume of the third grade

Algebraic expression addition and subtraction teaching plan

First, three-dimensional target.

(1) Knowledge and skills.

Can use the algorithm to explore the parenthesis rule, and use the parenthesis rule to simplify algebraic expressions.

(2) Process and method.

By analogizing the operation of rational numbers with brackets, the law of symbol change after removing brackets is found, and the law of removing brackets is summarized, thus cultivating students' ability of observation, analysis and induction.

(3) Emotional attitudes and values.

Cultivate students' awareness of active exploration, cooperation and communication and rigorous learning attitude.

Second, the importance, difficulty and focus of teaching.

1. key point: remove the bracket rule and apply it accurately to simplify algebraic expressions.

2. Difficulties: When there is a-sign in front of the brackets, when the brackets are removed, the symbols in the brackets are prone to errors.

3, the key: accurately understand the law of brackets.

Third, the preparation of teaching AIDS.

Projector.

Fourth, the teaching process, classroom introduction.

Polynomials can be simplified by combining similar terms. In practical problems, the listed formulas often contain parentheses. How to simplify them?

5. Newly awarded.

Now let's look at the questions in the introduction of this chapter:

On the Golmud-Lhasa section, if it takes t hours for the train to pass through the frozen soil section, it will take (t-0.5) hours to pass through the non-frozen soil section, so the distance between the frozen soil section and the non-frozen soil section is 120(t-0.5) km. Therefore, the total length of this railway is100t+120 (t-0.5) km. ① The difference between frozen area and unfrozen area is100t-120 (t-0.5) km. ② The above formulas ① and ② are enclosed in brackets. How should we simplify them?

Using the distribution law, you can delete brackets and merge similar items, and get:

100t+ 120(t-0.5)= 100t+ 120t+ 120(-0.5)= 220t-60