sinx= 4/5

π/2 <x<π


найти cos, tan, cot

sin^2x+cos^2x=1cos^2x=1-sin^2xcos^2x=1-(4/5)^2=1-16/25=9/25cosx=√9/25=3/5tgx =sinx/cosxtgx=4/5:3/5=4/3ctgx=cosx/sinxctgx=3/5:4/5=3/4