Respostas

  • Usuário do Brainly
2013-05-29T22:44:39-03:00

Temos que:

 

\text{A}=1-\sqrt{27}=1-3\sqrt{3}

 

\text{B}=1+\sqrt{75}=1+5\sqrt{3}

 

\text{C}=2-\sqrt{108}=2-6\sqrt{3}

 

Logo:

 

\text{A}+\text{B}+\text{C}=(1-3\sqrt{3})+(1+5\sqrt{3})+(2-6\sqrt{3})=4-4\sqrt{3}=4\cdot(1-\sqrt{3})

 

 

\text{A}-\text{B}-\text{C}=(1-3\sqrt{3})-(1+5\sqrt{3})-(2-6\sqrt{3})=-2-2\sqrt{3}

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