Use the method of variation of parameters to determine the general solution of the given differential equation. NOTE: Use c1, c2, and c3 as arbitrary constants.
y''' + y' = tan(t), -pi/2 < t < pi/2
Suppose the general solution is y(t) = yc(t) + Y(t), where
yc(t) = c1 + c2 cos(t) + c3 sin(t)
is the homogeneous solution and
Y(t) = -ln(cos(t)) + 1 - sin(t) ln(tan(t) + sec(t))
is the particular solution.