v.s.

mission impossible1 2 34 5 67 8 11 9 2

mission impossible Mission oneMission twoMission three

6,

1

2

1

3

4

2

2 =

51

1

2

logic

6

7

8ABCD ABCD (1) (2) or Why ?

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Relax

1Because , just now ,we knew the math in junior high school handles of numbers. But it is not enough.So !After that I know you will ask .

We have to learn new math concept in senior high school. For example:something that is right.Just now, We have learned how to prove something that is wrong . Now , we want to proveAbout logic, its key part islogic .proof.

2

8ABCD ABCD (1) (2) or Why ?

9ABC abc rr (1) (2) or Why ?

abarbrcr abrabc r 1

1817 1863 ()

?9

9ABC a bc r r ?

?

?

2abc2r

1 2 3

1

2

HPM ( History and Pedagogy of Mathematics )

Relax(50)

ABAB

loveI