Find the domain and the range of each of the following real function:
Given:
Need to find: Where the functions are defined.
Let, ---- (1)
To find the domain of the function f(x) we need to equate the denominator of the function to 0.
Therefore,
2 – x = 0
⇒ x = 2
It means that the denominator is zero when x = 2
So, the domain of the function is the set of all the real numbers except 2.
The domain of the function, Df(x) = (- ∞, 2) ∪ (2, ∞).
Now, to find the range of the function we need to interchange x and y in the equation no. (1)
So the equation becomes,
⇒
⇒
⇒
⇒
To find the range of the function f(x) we need to equate the denominator of the function to 0.
Therefore,
x + 1 = 0
⇒ x = -1
It means that the denominator is zero when x = -1
So, the range of the function is the set of all the real numbers except -1.
The range of the function, Rf(x) = (- ∞, -1) ∪ (-1, ∞).