This document provides an introduction to functions and their applications in economics. It defines a function as a formula or rule relating a dependent variable to an independent variable. Some common types of functions are described, including constant functions where the dependent variable does not change (e.g. y=5), and linear functions which have the form of y=a+bx and graph as straight lines (e.g. y=6+3x). The document states that in economics, quantities like demand, supply, costs and revenues are modeled as variables that depend on other factors, and can thus be represented as functions.

1. II ivaVa ivanayaona SaaoBato II
Janardan Bhagat Shikshan Prasarak Sanstha’s
Changu Kana Thakur
Arts, Commerce & Science College, New Panvel
Re-Accredited ‘A+’ Grade by NAAC
‘College with Potential for Excellence’ Status Awarded by University Grants Commission
‘Best College Award’ by University of Mumbai
Bridge Course
Mathematical & Statistical Techniques
By
Dr. S.I. Unhale
Associate Professor,
Department of Mathematics

2. Syllabus
Sr. No. Modules / Units
2 Functions and Their Applications
Functions: Constant function, linear function, Demand, Supply, Total Revenue
function, Total cost and Profit function and their applications. Quadratic functions
and equations.
Arithmetic and Geometric Progression

3. Topic: Functions and their Applications
Introduction: In Economics, we deals with quantities such as
amount of goods demanded in the market or supplied by a firm,
their cost of production, their prices, total income(Revenue) due to
their sale etc. Such quantities change their values. Hence, they are
called variables.
These variables are inter-related i.e. the value of one
depends on some other variable or variables. For example, suppose
the cost of production of a particular good depends on quantity of
good produced. Here, if ‘C’ is the cost of production and ‘x’ is the
quantity of good produced. Then the value of ‘C’ depends on the
value of ‘x’.
Here ‘C’ is called dependent variable and ‘x’ is called independent
variable and ‘C’ is function of ‘x’.

4. • In general, if the values of a variable ‘y’ depends on the
values of the variable ‘x’ then ‘y’ is the dependent variable
and ‘x’ is the independent variable. Also ‘y’ is said to be
function of ‘x’.
• Definition: Function: Function is nothing but some formula
or rule between dependent and independent variable.
• Functions are usually denoted by f, g, h, F, G etc.
• We write this as y = f(x).
e.g.: 1) y= 2x +5 or f(x) = 2x + 5.
2) y = 𝑥2
+ 2 x +5
are the functions.

5. Types of Functions
1) Constant function: The function of the type
y = C or f(x) = C , C is constant, is called a constant function.
e.g.: 1) y = 5 or f(x) = 5
2) y = 10 or f(x) = 10
are constant functions.

6. Types of Functions
2) Linear function: The function given as
y = a + b x or f(x) = a + b x , where a and b are constants
and b ≠ 0, is called a linear function. Graph of this function is
a straight line.
e.g.: 1) y = 6 + 3 x or f(x) = 6 + 3 x
2) y = 10 + 5 x or f(x) = 10 + 5 x
are linear functions.

7. THANK YOU