Answer:
i is √-1
Step-by-step explanation:
The definition of i is ...
i = √(-1)
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The i shows up in the solution of 2x² +1 = 0.
[tex]2x^2=-1\\\\x^2=\dfrac{-1}{2}=\dfrac{-2}{4}\\\\x=\pm\dfrac{\sqrt{-2}}{\sqrt{4}}=\pm\dfrac{\sqrt{(-1)(2)}}{2}=\pm\dfrac{\sqrt{-1}\cdot\sqrt{2}}{2}\\\\\boxed{x=\pm\dfrac{i\sqrt{2}}{2}}\qquad\text{use $i$ for $\sqrt{-1}$}[/tex]
