Question 990246
Lim x-> 4/7{-}{{{abs(4-7t)/(14t^2-8t)}}} 

=lim x-> 4/7{-}{{{(4-7t)/(-2t(-7+4))}}} Should be:  &#177{{{(4-7t)/(-2t(4-7t))}}}

=lim x-> 4/7{-}{{{-2t}}} Should be: &#177 {{{1/(2t)}}}

=lim x-> 4/7{-}{{{-2(4/7)}}}  Should be &#177 {{{7/8}}}
. 
You lost the absolute value and moved -2t to the top