Question

What is the square root of -9 in simplest form

Answer 1

It is 3i.
The square root of -9 is the square root of -1 times the square root of 9.
So: the square root of 9 is 3, and the square root of -1 is called i (this doesn't actually exist, it's just imaginary).
Then, the square root of -9 is 3i.

Answer 2

3i

Explanation:

Square root -9

√(-9) = (3i)(3i)

Note that the "imaginary number" is a non-existent number. Note that in the rules of imaginary numbers: i * i = i² = -1

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