Question 1032309
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I can't figure this type of trig question; evaluate inverse trig function when the number in the parenthesis is negative.  I can get the answer when it is not negative inside the parenthesis.  Help please!  

Example:  sin^-1 * (negative of the square root of two divided by two)

thanks. 
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<pre>
{{{arcsin(-sqrt(2)/2)}}} = -45°  or  {{{-pi/4}}}.


In general, {{{arcsin(-a)}}} = {{{-arcsin(a)}}}.
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