Вычислите

1) sin (-n/6) cos (-n/4) - sin (-n/4) cos (-n/6)

2) sin (-n/4) ctg (-n/4) - cos (-n/6) tg (-n/4)

3) sin (-n) + cos (-n/2) tg (-n/4) + ctg (-n/2)

1) sin (-n/6) cos (-n/4) - sin (-n/4) cos (-n/6) = - 1/2 * √2/2+√2/2*√3/2=√6/4-√2/4=√2/4 (√3-1) ;

2) sin (-n/4) ctg (-n/4) - cos (-n/6) tg (-n/4) = √2/2*1+√3/2*1=√2/2+√3/2=1/2 (√2+3) ;

3) sin (-n) + cos (-n/2) tg (-n/4) + ctg (-n/2) = 0-0*1-0=0.