one
Teaching preparation
Teaching objectives
1. Master the product of plane vectors and its geometric significance;
2. Master the important properties and operation rules of plane vector product;
3. Understand that the vertical problem can be handled by the product of the number of plane vectors;
4. Master the conditions of vertical vector.
Emphasis and difficulty in teaching
Teaching emphasis: the definition of quantity product of plane vector
Teaching difficulties: the definition of plane vector product, the understanding of operation law and the application of plane vector product.
teaching process
1. Definition of product (inner product) of plane vector: Two non-zero vectors A and B are known, and their included angle is θ.
Then the quantity |a||b|cosq is called the product of a and b, and it is denoted as a×b, that is, a×b=|a||b|cosq, (0≤θ≤π).
And specify that the product of 0 vector and the number of arbitrary vectors is 0.
× Inquiry: 1. Is the product of vectors a vector or a quantity? When is its symbol positive? When is it negative?
2. What is the difference between the product of two vectors and the product of real numbers multiplied by vectors?
(1) The product of two vectors is a real number, not a vector, and the sign is determined by the sign of cosq.
(2) The quantitative product of two vectors is called the inner product, and it is denoted as a× b; In the future, we should learn the outer product of two vectors. a×b and a×b are the products of the numbers of two vectors, and we should strictly distinguish them when writing. The symbol "×" is not a multiplication symbol in vector operation, so it can neither be omitted nor replaced by "×".
(3) In real numbers, if a? 0, and a×b=0, then b = 0; But in the product of quantities, if a? 0, and a×b=0, we can't deduce that b=0, because cosq may be 0.
two
Teaching preparation
Teaching objectives
1. Master the product of plane vectors and its geometric significance;
2. Master the important properties and operation rules of plane vector product;
3. Understand that the problems of length, angle and verticality can be solved by the product of plane vectors;
4. Master the conditions of vertical vector.
Emphasis and difficulty in teaching
Teaching emphasis: the definition of quantity product of plane vector
Teaching difficulties: the definition of plane vector product, the understanding of operation law and the application of plane vector product.
teaching tool
projector
teaching process
First, review the introduction:
1. vector * * line Theorem vector and non-zero vector * * * line have only one non-zero real number λ, so = λ.
Fifth, class summary.
(1) Let the students review what they have learned in this lesson. What are the main mathematical thinking methods involved?
(2) In the learning process of this class, there are still some places you don't quite understand, please ask the teacher.
How did you do in this class? What was your experience?
Sixth, homework after class
P 107 Exercise 2.4A Group 2 and Group 7 Questions
Summary after class
(1) Let the students review what they have learned in this lesson. What are the main mathematical thinking methods involved?
(2) In the learning process of this class, there are still some places you don't quite understand, please ask the teacher.
How did you do in this class? What was your experience?
homework
homework
P 107 Exercise 2.4A Group 2 and Group 7 Questions
Write on the blackboard.
leave out