Complex numbers emerge when you take the square root of a negative number, since the imaginary unit [tex]i[/tex] is defined by the relation [tex]i^2=-1[/tex], which implies [tex]\sqrt{-1}=i[/tex]
The only option involving the square root of a negative number is the last one.
Answer:
option D
Step-by-step explanation:
Complex number is a number that has negative under the square root.
Square root (-1) =i is a complex number
square root of a negative number is a complex.
First option does not have any negative number under the square root so it is not a complex.
second option also not have negative number under square root . So it is not a complex
third option have positive 7 under the square root so it is not a complex
Fourth option have -9/5 under the square root . So it is a complex number
