1.Which of the following is an empty set?a.{x : x² + 1 = 0, x ∈ R}b.{x : x² − 9 = 0, x ∈ R}c.{x : x² = x + 2, x ∈ R}d.{x : x² − 1 = 0, x ∈ R}Login to continueOnly logged in users canattempt or see the solution.
