Final Answer:
Complementary function of the differential equation: yc(θ) = A cos(θ) + B sin(θ)
General solution of the differential equation: y(θ) = yc(θ) + y particular(θ)
Solving the differential equation by variation of parameters: y(x) = C₁ cos(x) + C₂ sin(x) - (1/2) sin(2x)
Step-by-step explanation:
For the differential equation y" + y = sec(θ) tan(θ), the complementary function (yc) is derived from the homogeneous equation y" + y = 0, resulting in yc(θ) = A cos(θ) + B sin(θ). This represents the solution to the associated homogeneous differential equation. The general solution of the differential equation combines the complementary function with a particular solution (yp) obtained from the non-homogeneous part of the equation. The general solution is given by y(θ) = yc(θ) + y particular(θ).
Now, for solving the differential equation y" + y = sin^2(x), the complementary function yc(θ) = A cos(θ) + B sin(θ) remains the same. However, the particular solution for this equation, found using variation of parameters, is y particular(θ) = -(1/2) sin(2θ). Hence, the general solution for this equation becomes y(θ) = yc(θ) + y particular(θ) = C₁ cos(θ) + C₂ sin(θ) - (1/2) sin(2θ).
In summary, the complementary function represents the solution to the associated homogeneous equation, while the general solution incorporates both the complementary function and the particular solution obtained through methods like variation of parameters to solve non-homogeneous differential equations."".