Question 1178878
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<pre>

Geometrically, the angle  {{{-5pi/2}}}  is the same as  {{{-pi/2}}}.



Therefore,  {{{sin(-5pi/2)}}} = {{{sin(-pi/2)}}} = -1.


arctan(-1) = {{{-pi/4}}}.                     <U>ANSWER</U>


{{{tan^(-1)(-1)}}} = {{{-pi/4 + k*pi}}}.            <U>ANSWER</U>
</pre>

Solved, answered and explained.