Find the maximum and minimum values of `f(x)=x^3-1` on `R` , if any, without using derivatives.

Explanation

Neither maximum nor minimum value exist for the given function f(x) as

`x^3 rightarrow infty` for `x rightarrow infty` and `x^3 rightarrow -infty` for `x rightarrow -infty`

Then, `f(x) rightarrow infty`for `x rightarrow infty`and

`f(x) rightarrow -infty`for `x rightarrow -infty`