Question

Which of the following is a singleton set?

(a) {: || < 1, ∈ }
(b) {: || = 5, ∈ }

(c) {:
² = 1, ∈ }
(d) {:
² + + 1 = 0, ∈ }​

Answer 1

Answer:

{: || = 5, ∈ }

Step-by-step explanation:

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