If sin(t)=4/5 & 0<t<pi/2, find the following: a)sin t(-t) b) sin(t-2pi) c)cos t d)cos(pi-t)

sin(-t) = -sin(t) = -4/5

sin(t-2pi) = sin(t) = 4/5
cos(t) = 3/5
cos(pi-t) = -3/5