Transformations of Functions

In this page we are going to discuss about transformations of functions concept . Function is defined as one quantity (input of transformations functions) associated with another quantity (output of transformations functions). The quantity can be a Real numbers or Elements from any given sets or the domain and the co domain of the function.

For Example: The function is defined as f : C -> D is a relation that assigns to each x belongs to C to y belongs to D. C is Domain of f and D is Range of f.


Types of transformations of functions

There are four classes of transformations,

1. Horizontal translation: The function is transformed along X axis.

g (x) = f (x + c)

It means that the graph is translated c values to the left side for c > 0 or to the right side for c < 0.

2. Vertical translation: The transformation of function is along Y axis.

g (x) = f (x) + k

It means that the graph is translated k values upwards for k >0 or downwards for k < 0.

3. Change of amplitude:

g (x) = b f (x)

It means that the amplitude of the graph is increased by a factor of b if b > 1 and decreased by a factor of b if b < 1, if b < 0, then we get inverted graph.

4. Change of scale:

g (x) = f (cx)

It means that the graph is compressed if c > 1 and stretched out if c < 1. If c < 0 then we get the reflected graph about y axis.

Examples

Below are the examples on transformations of functions -

Examples:

Examples for functions include parabolas, trigonometric curves and polynomial functions.

* f (x) = 2x2 , for all x values are real

* f(x) = y + sin x, x ,y are real.

* f (x) = 1 / (x+1), for all real numbers except -1

*f (x) = x3-4x2+9x , Polynomial function


Even or Odd Functions

A function f:C-->D is said to be even if and only if f (-x) = f (x) for all x belongs to C.

A function is said to be odd if and only if f (-x) = -f(x) for all x belongs to C.

Even function is symmetric about the y-axis; an odd function is symmetric about the origin in the graph.

Example :  * f (x) = 2x2 is an even function.

* f (x) = x + sin x is odd.