The square root of minus 1

The symbol is

It is a number that, when multiplied by itself, produces −1

But when we square any Real Number we always get a positive, or zero, result. For example:

• 2 × 2 = 4, and

• (−2) × (−2) = 4 also.

So how can we square a number and get a negative result? Just "imagine" that we can, and it turns out that such a number, which may seem impossible, is actually useful and can solve real problems.

The symbol is

**i**It is a number that, when multiplied by itself, produces −1

But when we square any Real Number we always get a positive, or zero, result. For example:

• 2 × 2 = 4, and

• (−2) × (−2) = 4 also.

So how can we square a number and get a negative result? Just "imagine" that we can, and it turns out that such a number, which may seem impossible, is actually useful and can solve real problems.

See: Real Number

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