Question 638275
1. sqrt(27) + 2sqrt(5) - sqrt(75)
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= sqrt(9*3) + 2sqrt(5) - sqrt(25*3)
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= 3sqrt(3) + 2sqrt(5) - 5sqrt(3)
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= 2sqrt(5) - 2sqrt(3)
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2. sqrt(5/4)
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= sqrt(5)/sqrt(4)
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= sqrt(5)/2
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= (1/2)sqrt(5)
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3. sqrt(4/5)
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= sqrt(4*5)/sqrt(5*5)
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= 2sqrt(5)/5
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= (2/5)sqrt(5)
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Cheers,
Stan H.