To facilitate the relationship between these variables, then the way
This economic model
can form a mathematical model.
Variables are denoted by letters. endogenous and exogenous variables. the solution obtained from the model, while the exogenous variables is a
variable whose values obtained from outside the model, or has been determined based on data
existing. Constant is a real number whose value does not change in a model
Parameter is defined as a specific value in a specific problem and
probably will be another value at some other issues.
B. EQUATIONS AND INEQUALITIES
Mathematical models often include a statement or group of statements
then these sections individually called tribes (terms). within each tribe. product.
is the number 10.
The rules of logarithms
1. xlog x = 1
2. xlog 1 = 0
3. xlog xa = a
4. ma = a xlog xlog m
5. x xlog m = m
6. mn = xlog xlog xlog m + n
7. xlogm/n - xlog m - xlog n
usually expressed by mathematical functions. Function in mathematics
declare a formal relationship between the two sets of data. If the set of data
is variable, then the function can be considered as relations between the two
Function is a form of mathematical relationships which express the relationship
dependence (functional relationship) between the one variable with another variable.
Variable and the coefficient is always present in every function.
Variables are building blocks for functions which reflect or represent the factors
(Data), specific, denoted by Latin letters. Based on the position or
nature, in every function, there are two kinds of variables: independent variables
(Independent variable) and dependent variable (dependent variable). is a variable whose value does not depend on other variables, whereas variables
bound is a variable whose value depends on other variables.
The coefficient is a number or numbers related to and located in front of a
variable in a function.
Constants are numbers or number (sometimes) helped shape
y = 5 + 0.8 x
y: dependent variable
x: independent variable
While the notation of a general function is: y = f (x)
Cartesian Coordinate Systems
Each function can be presented graphically on a pair of field axis
cross (coordinate system). Images of a function can be generated by
calculate the coordinates of the points that satisfy the equation, and then
couples moving point to cross-axis system. In
1. 2. 3.
these. used for the completion of a system of linear equations, namely: (1). Substitution (2). Elimination Methods, and (3). The determinant method.
x +4 y = 23!
For example equation
Then substituted into the equation one.
x = 23-yr 4y = 21 2x + 3 Y
2 (23-4y) + 3 Y = 21
46 - 8y + 3 Y = 21
46 - 5Y = 21
25 = 5Y
y = 5
y = 5 Þ 2x + 3y = 21
2x + 3(5) = 21
2x + 15 = 21
2x = 21 – 15
x = 6/2
x = 3
2x +4 y = 10!
3x - 2y = 7 x 2 6x - 4y = 14
2x + 4y = 10 x 1 2x + 4y = 10 +
8x + 0 = 24
x = 3
x = 3 Þ 3(3) - 2y = 7
-2y = 7 – 9
2y = 2
y = 1