Compute the exact value of each of the following. (Type sqrt(2) for $\displaystyle \sqrt{{{2}}}$ and sqrt(3) for $\displaystyle \sqrt{{{3}}}$.)

$\displaystyle {\sin{{\left(\frac{{-{25}\pi}}{{{6}}}\right)}}}=$ Preview Question 6 Part 1 of 3  

$\displaystyle {\cos{{\left(\frac{{-{25}\pi}}{{{6}}}\right)}}}=$ Preview Question 6 Part 2 of 3  

$\displaystyle {\tan{{\left(\frac{{-{25}\pi}}{{{6}}}\right)}}}=$ Preview Question 6 Part 3 of 3