Respostas

2014-05-02T18:43:22-03:00
p(x)=2x^3-x^2+x+3


p(2)=2(2)^3-(2)^2+(2)+3\\p(2)=17

p(-1)=2(-1)^3-(-1)^2-1+3\\p(-1)=-1

p( \frac{1}{2} )=2( \frac{1}{2} )^3-( \frac{1}{2} )^2+ \frac{1}{2} ++3\\\\
p( \frac{1}{2} )= \frac{7}{2}


Substituindo na expressão

 \frac{p(2)-2p(-1)}{p( \frac{1}{2} )}


\boxed{ \frac{17-2(-1)}{ \frac{7}{2} } ~\to~ \frac{19}{ \frac{7}{2} } ~\to~ \frac{19.2}{1.7} ~\to~ \frac{38}{7} }

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