The domain of the function which is represented by the graph is:
All real numbers ( In interval form (-∞,∞) )
We know that a domain of a function is the set of the all the x-values for which the function is defined.
By looking at the graph of the function we see that it is a graph of a upward open parabola and the graph is extending to infinity on both the side of the x-axis this means that the function is defined all over the x-axis i.e. for all the real values.
Also, we know that the function will be a quadratic polynomial since the equation of a parabola is a quadratic equation and as we know polynomial is well defined for all the real value of x.
Hence, the domain of the function is:
All real numbers (In interval form (-∞,∞) )
