Question 974665
{{{(tan(3pi/4)-tan(pi/12))/ (1+tan(3pi/4)tan(pi/12))}}}
={{{tan(3pi/4 - pi/12)}}} (Since  tan(A-B)=[tan A - tan B ] / [ 1 + tan A tan B]
={{{tan(2pi/3)}}}
={{{-sqrt(3)}}}