а)sina = -3/5tga = sina/cosa = 3/5 : 4/5 = 3/4 б)cosa = 5/13
tga = sina/cosa = -12/13 : 5/13 = -12/5
в)
а)





sina = -3/5
tga = sina/cosa = 3/5 : 4/5 = 3/4
б)
cosa = 5/13
tga = sina/cosa = -12/13 : 5/13 = -12/5
в)