Question 414406
2) and 4) are not real because they both
have {{{sqrt(-1)}}} in the expressions
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2)
{{{ sqrt(-64) = sqrt(64)*sqrt(-1)}}}
{{{sqrt(-64) = 8i}}}
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4)
{{{3*sqrt(-64) = 3*8*sqrt(-1)}}}
{{{3*sqrt(-64) = 24i}}}