Graph of Functions

We can present functions in graphical form through substituting all input values as x-axis and all output values as y-axis.  Where y = f(x).

We plot the graph of function in similar way we plot the graph for equations.

The graph of a function is being written like

  • f(x) = 2x -1
  • f(x)  = √x+2
  • g(x) = x2 + 1/3
  • h(x) = x3  -1

Example 1

Graph of function     f(x) = 3x -2    where   x ≥ 1

Answer ;  First make table to get the x and y  coordinates

x f(x) = y = 3x – 2  ( x , y )
1 1 ( 1 , 1 )
2 4 ( 2 , 4 )
3 7 ( 3 , 7 )
4 10 ( 4 , 10 )

g2

Example 2

Plot the graph of the function given by y = 2m2 + 2, where -2 ≤ m ≤ 2.

Answer ;

First make table to get the x and y coordinates

x f(x) = y = 2m2 + 2  ( x , y )
-2 10 (-2 , 10)
-1 4 ( -1 , 4 )
0 1 ( 0 , 1 )
1 4 ( 1 , 4 )
2 10 ( 2 , 10 )

g6

Example 3             Plot the graph of function of   f(x) = x2

Answer

x                 f(x)

-2                  4

-1                  1

 0                  0

 1                   1

 2                   4

g5

Exercise ;

Plot the graph of function of the following

  1. f(x) = √ x
  2. f(x) = │x│
  3. f(x) = 1/x
  4. f(x) = 5x -1 , for  -2 ≤x ≤ 4
  5. f(x) = 5 – m2 , for 1≤m≤4
error: