Math 9, Lesson 13, Fall Semester, 12/18/2016

Weidong Posted in Fall 2016, Homework, Teaching info，
18 December 2016
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We review Set Language and Matrices.

A set is a well-defined collection of distinct objects. We talk about how to describe a set, the concept of an element, a subset, when two sets are equal. We also talk about the universal set, the empty set, the complement set for a set, the set union and intersection operations.

We talk about the Venn diagram to represent sets.

We also go over some more practice with matrices.

Homework: From the three page2 below: #1 – #5, #11 – #14, #15 – #17

Page 1, Page 2, Page 3, Page 4

Answers to last week’s homework: Please see Lesson 11’s answer pages.

 

Math 9, Lesson 12, Fall 2016, 12/11/2016

Weidong Posted in Fall 2016, Homework, Teaching info，
11 December 2016
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We spend more time on matrix multiplication by doing more practice questions.

Homework:

Workbook Page 23, #14 – #16, #20, #22 – #24. Please use Lesson 10’s homework pages for the questions.

Answers to last week’s homework: Please see Lesson 11’s answer pages.

 

Math 9, Lesson 11, Fall 2016, 12/04/2016

Weidong Posted in Teaching info，
03 December 2016
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We study multiplication of a matrix by a scalar and multiplication of two matrices.

A matrix can be multiplied by a real number (usually called a scalar). If k is a scalar, then the scalar multiplication of a matrix A by k, denoted by kA, is obtained by multiplying every element of A by k.

Matrices multiplication is defined as follows:

If A is a matrix of order m x n and B a matrix of order n x p, then the product AB is a matrix of order m x p whose element at the ith row and jth column is the sum of the products of the corresponding elements in the ith row of A and jth column of B.

If the column number of A is not equal to the row number of B, then AB is undefined.

We introduce Identity Matrix of order n, which has 1 on its major diagonal line and 0 anywhere else..

Homework:

Workbook Page 21, #7, #10 – #12, #18, #19. Please use last lesson’s homework pages for the questions.

Answers to last week’s homework: Answers1  Answers2