5th grade
Natural numbers
Basic arithmetic operations
Calculation laws and advantages
Geometry

6th grade
Divisibility of numbers
Factions
Decimal fractions
Angles and angle measures

7th grade
Assignment and rule of three
Calculation of percentage
Rational numbers
Equation and inequation
Probability calculus

8th grade
Function and assignment
Triangles
Quadrangles
Calculation of surfaces
Transformation of terms
Probability calculus

9th grade
The root
Record set of the pythagoras

10th grade
Circle calculation
The cone
Power calculation
Power laws
Exponential function
Logarithm
Trigonometry
Probability calculus

 

Exponential function
f(x) = ax

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The precept

f (x) = ax

  

The Graph

The simplest example is: f (x) = 2x

In values, that means:

x

- 1

0

1

2

3

4

5

y/ax

½

1

2

4

8

16

32

That means that a number 2 to the power of an x-value makes the y-value. If the y-value is given and the x-value (is 2|4 for example), the reciprocal calculation must be used: the root! The second root (the normal one) of the x-value = 2, and x = 3, the third root, so on and so forth, from the respective y-value (in this example, it is the third root of 8 and the fourth root of 16).

 

Another (more difficult) example

The points 2|2 and 4|4 can be read off quite clearly. Following the precept given above, the calculations would be following.

or:

The function, in which a < 1

If the base is smaller then one (but also bigger than 0), the values are similar to the values where the base is bigger than one, just the reciprocal value of it!

 

Base bigger than 1

Example: 2

Base smaller than 1

Example: 0,5

x

y

x

y

- 1

½

- 1

2

0

1

0

1

1

2

1

0,5

2

4

2

0,25

3

8

3

0,125

4

16

4

0,0625

5

32

5

0,03125

 

The Graph

This is what it would look like in the coordinate system (to be exact, it is only a reflection on the y-axis):

 
 

Copyright © 2005 Christian Franzki - Emkacom Group
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02/09/07