E-STAR - Student

If a function is defined by f (x) = -x² +2x+1, which of the following is the range of this function?

{y ∈ ℝ | y ≥ 1}

{y ∈ ℝ | y ≤ 1}

{y ∈ ℝ | y ≥ 2}

{y ∈ ℝ | y ≤ 2}