A function `f : RrarrR` is defined as `f(x) = x^(2) +2`, then evaluate each of the following :
(i) `f^(-1)(-6)` (ii) `f^(-1)(18)`

Explanation

(i) `f^(-1)(-6)={x in R : f (x) =-6}`
= `{x in R : x^(2) + 2 =- 6}`
= `{x in R : x^(2) =- 8} = phi` Ans.
(ii) `f^(-1)(18)= {x in R : f(x) = 18}`
= `{x in : x^(2) + 2 = 18 } = {x in R : x^(2) = 16 }`
= `{x in R : x = +- 4 } = {-4,4}`. Ans.