Realistic Mathematics Education (RME)

INTRODUCTION

Realistic Mathematics emphasizes the construction of the context objects as a starting point for students to acquire mathematical concepts. Concrete objects and objects of environment can be used as a context for learning mathematics in building mathematical connection through social interaction. According to Hans Freudental in Marsigit (2009) mathematics is human activities and should be linked to reality. Thus when students do activities to learn mathematics will occur itself a mathematical process.

CONTENT

The part of Realistic Mathematics Education, among others:

A.    Formal Mathematics

Formal mathematics is agreement in mathematics for use in the learning of mathematics. For example are mathematics symbol, theorems, axioms, formula, and understanding about mathematics.

Based on the book Mathematics for Junior High School grade 2 by Marsigit on page 173, a circle is a set of points that have the same distance to a fixed point. This fixed point is called the centre of circle.

The part of circle, among others:

1.      Centre of circle

The central point of the circle is given the symbol O.

2.      Radii

Radius is the distance between a point on the circle with the centre of circle.

3.      Diameter

Diameter is a line through the centre of the circle and connecting two points on a circle.

4.      Chord

Chord is a line segment that connecting two points on a circle.

5.      Apothem

Apothem is line segment drawn from the centre of circle and perpendicular to the chord.

6.      Sector

Sector is an area bounded by two radii and an arc.

7.      Segment

Segment is an area bounded by a chord and an arc.

8.      Minor arc

Minor arc is the arc that limited the minor sector and minor segment.

9.      Major arc

Major arc is the arc that limited the major sector and major segment.

10.  Minor Sector

Minor sector if its central angle size is less than 180⁰.

11.  Major Sector

Major sector if its central angle size is more than 180⁰.

12.  Minor Segment

13.  Major Segment

Circumference of a circle formula is: K = π.d = 2.π.r

With:

K = circumference of a circle

r = radius of the circle

d = diameter of the circle = 2r

π ≈ 3,14

Area of a circle formula is: L = π.r² =  π.d²

With:

L = area of the circle

r = radius of the circle

d = diameter

π =  ≈ 3,14

B.     Formal Model of Mathematics

Formal Model of Mathematics is a mathematical model of the agreements in the learning of mathematics. Based on the book Mathematics for Junior High School grade 2 by Marsigit, example of formal model of mathematics is like the figure shown below.

Point O is called centre of circle

OR, OT, OP is called radii

TP is called diameter

TR is called chord

OI is called apothem

Area of TRO is called sector

Area of TRI is called segment

TR is called minor arc

TPR is called major arc

           

Source: Marsigit’s book page 173

Figure 1 The circle parts

C.     Concrete Model of Mathematics

Concrete Model of Mathematics is a concrete object that is a model of a topic in mathematics. Based on the book Mathematics for Junior High School grade 2 by Marsigit, example of concrete model of mathematics is like the figure shown below.

       

Source: Marsigit’s book page 173

Figure 2 Tyres and CDs are examples of circle shaped things

D.    Concrete Mathematics

Concrete Mathematics is a real form or the application of the mathematics concepts in everyday life. Based on the book Mathematics for Junior High School grade 2 by Marsigit, example of concrete mathematics is like the figure shown below.

Source: Marsigit’s book page 175

Figure 3 The distance you have passed when walking around the circle fountain is the circumference of a circle

CONCLUSION

The part of Realistic Mathematics Education is formal mathematics, formal model of mathematics, concrete model of mathematics, and concrete mathematics.

REFERENCE

Marsigit. 2009. Mathematics for Junior High School Grade 2. Yudhistira: Yogyakarta.

Marsigit. 2009. “Pemanfaatan Video Tape Recorder (VTR) untuk Pengembangan Matematika Realistik di SMP”. [Online]. Tersedia: http://staff.uny.ac.id. [3 Maret 2012].