1. Form 1 Mathematics Chapter 2 and Chapter 4

2. “>”: is greater than -2 -6 47 0 +– 7 -2 4 0 > say “seven is greater than minus two” > say “four is greater than zero”

3. “<”: is less than -2 -6 47 0 +– -6 4 -2 0 < say “minus six is less than four” < say “minus two is less than zero”

4. Ronald HUI  If we say number of students in Form 1 is greater than 150, we can write the following inequality:  Let x be the number of students in Form 1.  Then, x > 150  Do we know the exact number of students?  It can be 151, 152, 153, 160, 170, 200, 300!

5. Ronald HUI  The amount of money Mr. Hui has is less than $500. What is the inequality?  Let R be the amount of money Mr. Hui has  Then, R < 500  Do we know how much Mr. Hui has now?  It can be $499.90, $300, $10, $0!

6. Ronald HUI  “  ”: Greater than or equal to ◦ A combination of “>” and “=”  “  ”: Less than or equal to ◦ A combination of “<“ and “=”

7. Ronald HUI  Some important concepts  Is it true that “Not less than” means “Greater than”? ( 「不少於」是否等同「多過」呢？ )  How about “Not Greater than” means “Less than”? ( 「不多於」是否等同「少過」呢？ )

8.  Page 165 of Textbook 1A ◦ Questions 1 - 8  Page 77 of WB 1A ◦ Questions 1 - 4

9. Ronald HUI  The use of variables to write a sentence telling us instruction to do a calculation is a Formula.  E.g. The area of a rectangle ( 長方形 ) is its length ( 長 ) times its breadth ( 闊 ).  If Area is A, length is L and breadth is B,  Then, A = L  B (or simply A = LB)

10. Ronald HUI  A = L  B  A is the subject of the formula  L and B are the variables of the formula  If L = 5 cm, B = 3 cm, we have  A = L  B = (5 cm)  (3 cm) = 15 cm 2  It is called method of substitution ( 代入法 ).

11. Ronald HUI  Can you suggest a formula for the followings?  Area of a square ( 正方形 )  Area of a triangle ( 三角形 )  Area of a trapezium ( 梯形 )  Perimeter ( 周界 ) of a rectangle  Perimeter ( 周界 ) of a circle  Area of a circle

12.  Page 169 of Textbook 1A ◦ Questions 5 - 14  Page 80 of WB 1A ◦ Questions 1 - 5

13.  SHW (I), SHW (II) (Chapter 4) ◦ 12 Nov (Monday)  Open Book Quiz (Chapter 4) ◦ 14 Nov (Wednesday)  Close Book Quiz (Chapter 4) ◦ 21 Nov (Wednesday)  You must hand in on time!

14. Good Luck! Enjoy the world of Mathematics! Ronald HUI