Which of the following is not a real number?
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Answer:
The answer is A, Square root of -3 is not a real number.
Step-by-step explanation: You can take the square root of positive numbers, so we can eliminate choices C and D. We can take the square root of 0, which would equal 0, so B is incorrect. However, We cannot take the square root of negative numbers, so choice A is the answer for this question.