You can put this solution on YOUR website! (sqrt 18)/(2isqrt 6)
= 3sqrt(2)/2isqrt(6)
What you do now depends on the statement of the problem.
You could multiply numerator and denominator by -2isqrt(6)
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If you want to do that you would get:
= [(3sqrt(2)(-2isqrt(6)] / (-4i^2*6)
= [-6isqrt(12)] / (24)
= [-6*2isqrt(3)]/24
= [-isqrt(3)/2]
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Cheers,
Stan H.