Q14 of 99 Page 34

Find the domain and range of the function

F : R → R : f(x) = x2 + 1.



Since the function f(x) can accept any values as per the given domain R, therefore, the domain of the function f(x) = x2 + 1 is R.


The minimum value of f(x) = 1


⇒Range of f(x) = [ - 1,∞]


i.e range (f) = {y ∈ R : y ≥ 1}


Ans: dom (f) = R and range (f) = {y ∈ R : y ≥ 1}


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