# Where is the error?

Algebra Level 2

I am performing the following steps to prove $$-1 = 1:$$

1. $$-1 = i^{2}$$
2. $$-1=i \times i$$
3. $$-1 = \sqrt{-1} \times \sqrt{-1}$$
4. $$-1 =\sqrt{-1 \times -1}$$
5. $$-1 =\sqrt{1}$$
6. $$-1=1.$$

In which step does the error exist?

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