А) cos(a) = 4/5, tg(a) = 3/4, ctg(a) = 4/3
б) sin(a) = 4/5, tg(a) = -4/3, ctg(a) = -3/4
в) sin(a) = 15/17, tg(a) = 15/8, ctg(a) = 8/15
г) sin(a) = 3√10/10, cos(a) = √10/10, ctg(a) = 1/3
д) cos(a) = -2√2/3, tg(a) = -√2/4, ctg(a) = -2√2
е) sin(a) = -1/2, cos(a) = √3/2, ctg(a) = -√3
ж) sin(a) = -2√29/29, cos(a) = 5√29/29, tg(a) = -2/5