roots

Problem Solving — algebra and arithmetic (GMAT Focus Edition)
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roots

by aerodan1 » Thu Apr 08, 2010 5:54 pm
if you have sq. rt. (27), how can you reduce that to (3)(sq. rt. (3)) ? i know to reduce it to to 3^(3/2), and then to 3^1.5, but am just a little foggy with all the different ways to express numbers that involve square roots.
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by thephoenix » Thu Apr 08, 2010 6:05 pm
sqrt(27)=sqrt(3*3*3)=sqrt[(3^2)*(3)]=sqrt(3^2)*sqrt(3){sqrt(xy)=sqrt(x)*sqrt(y)}=3sqrt(3)