Christmas Streak 69/88: Where is wrong? #2

Algebra Level 3

Picture is drawn by me.

$\text{Where is wrong?}$

Notation: $i$ is the imaginary unit.

\sqrt{(-1)\times(-1)}=\sqrt{1}

Nothing's wrong

i^2=i\times i

\sqrt{-1}\times\sqrt{-1}=\sqrt{(-1)\times(-1)}

i\times i=\sqrt{-1}\times\sqrt{-1}

-1=i^2

\sqrt{1}=1

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