In Example 3, put a − sign before the first radical of the first illustration and then simplify.

Data from Example 3

To further illustrate the method of handling square roots of negative numbers, consider the difference between

For these expressions, we have

For √−3 √−12, we have the product of square roots of negative numbers, whereas for √(−3)(−12), we have the product of negative numbers under the radical. We must be careful to note the difference.

-3-12 and (-3)(-12).