y=cos(9/2π+x)+sinx=cos(π/2+x)+sinx=-sinx+sinx=0=max=min
y=cos(9/(2π)+x)+sinx=cos(9/(2π))cosx-(sin(9/(2π))-1)sinx
=(-√(cos(9/(2π)))^2+(sin(9/(2π))-1)^2)cos(x-c)
tanc=(sin(9/(2π))-1)/cos(9/(2π))
ymin=-√(cos(9/(2π)))^2+(sin(9/(2π))-1)^2
ymax=√(cos(9/(2π)))^2+(sin(9/(2π))-1)^2