<PRE><B>Question 257188</B>
Work from the inside out.
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(1-(2-(1-(2(-1)))))}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(1-(2-(1-(-2))))}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(1-(2-(1+2))))}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(1-(2-(3)))}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(1-(-1))}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(1+1)}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=2-(2)}}}
{{{ 2-(1-(2-(1-(2(1-2)))))=0}}}
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