Yes, you can; based on the inherent assumption that the "two radicals that have negative values" are, in fact, "imaginary numbers" .
Take, for example, the commonly known "imaginary number": "i" ; which represents the "imaginary number" ; " √-1 " .
Since: "i = √-1" ;
Note that: " i² = (√-1)² = √-1 * √-1 = √(-1*-1) = √1 = 1 .
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