Question 982122
{{{ y = 2^x - 2^(-x) }}}
{{{ x = log(2,(1 - y)) }}} --> {{{2^x = 1 - y}}}
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{{{ y = 2^x - 2^(-x) }}}
{{{ y = (1-y) - 1/(1-y) }}}
{{{y*(1-y) = (1-2y+y^2) - 1}}}
{{{y - y^2 = y^2 - 2y}}}
{{{2y^2 - 3y = 0}}}
y = 0, x = 0
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y = 3/2, x = undefined