Rewriting a number using i

The video tutorial explains how to simplify numbers using the imaginary unit I. It introduces a key rule for square roots, which states that the square root of a product can be split into the product of square roots. This rule is applied to simplify sqrt(-4) by breaking it into sqrt(4) and sqrt(-1), where sqrt(-1) is the imaginary unit I. The tutorial concludes by rewriting sqrt(-4) as 2i, demonstrating the use of the imaginary unit in simplifying complex numbers.

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