Question 68781
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{{{2(1/2)^2 + (-1/2) -1}}}

{{{2(1/(2*2)) + (-1/2) -1}}}

{{{2(1/4) + (-1/2) - 1}}}

{{{2/4 -(1/2)-1}}}

{{{1/2 - 1/2 - 1}}}

-1

Therefore, {{{2(1/2)^2 + (-1/2) -1 = -1}}}
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