Question 383978
{{{f(x)=2x^3 +x^2-x-5}}}
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{{{f(1)=2(1)+1-1-5}}}
{{{f(1)=-3}}}
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{{{f(2)=2(8)+4-2-5}}}
{{{f(2)=13}}}
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Since {{{f}}} changes sign, it must equal zero within the interval.