CAT Graphical representation of a function - Practice Questions & MCQ

A graph represents a function, if there exists a vertical line which meets the graph in not more than two or more points, i.e., a vertical line meets the graph at only one point.

In this diagram, the vertical dotted line meets the graph at only one point. So the Y-axis represents a function.

Identity Function

Let R be the set of real numbers. Define the real valued function by for each . Such a function is called the identity function. Here the domain and range of f are R.

The graph is a straight line and passes through the origin.

Constant Function:

Define the function by where c is a constant and each . Here the domain of f is R and its range is { c }.

The graph is a line parallel to x-axis.

Tips and Tricks for Graphical Representation of Functions

• Tip 1: Familiarise yourself with the basic function shapes
• Tip 2: Pay attention to the intercepts and endpoints
• Tip 3: Understand the effects of transformations on function graphs
• Tip 4: Practise analysing function graphs through real-life applications