The domain of f(x) means those possible values which can be assigned to x, such that f(x) is defined for all such values, or in other words value of f(x) remains Real.

In the given function f(x) will be Real for all Real values of x. Hence the Domain of f(x) is R. In set notation it is (-∞,∞ )

Since f(x) =x, f(x) can have all those values which x can have. The values which f(x) can have is called the Range of f(x). Here the Range of f(x) will also be R.

Since Domain and Range of f(x) is R, there is no point of discontinuity. Discontinuity occurs when for any real value of x , f(x) ceases to exist or ceases to be a real number.

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