Question 440121
2 radical 27- 3 radical 48 
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27 factors as 9*3
48 factors as 16*3
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Your Problem:
2*sqrt[9*3] - 3*sqrt(16*3)
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= 2*3*sqrt(3) - 3*4*sqrt(3)
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= 6sqrt(3) - 12sqrt(3)
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= -6sqrt(3)
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Cheers,
Stan H.
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