Asksia AI LOGO

Sia

gracecheng11's Question
Math
Posted 3 months ago
Solve the differential equation y4y+4y=e2xy'' - 4y' + 4y = e^{2x} using the method of undetermined coefficients.
Sign in to unlock the answer
Answer from Sia
Posted 3 months ago
Solution by Steps
step 1
We start with the differential equation y4y+4y=e2xy'' - 4y' + 4y = e^{2x}. The complementary solution is found by solving the homogeneous equation y4y+4y=0y'' - 4y' + 4y = 0, which has a characteristic equation (r2)2=0(r - 2)^2 = 0. Thus, the complementary solution is yc(x)=c2e2xx+c1e2xy_c(x) = c_2 e^{2x} x + c_1 e^{2x}
step 2
Next, we find a particular solution using the method of undetermined coefficients. We assume a particular solution of the form yp(x)=Ax2e2xy_p(x) = A x^2 e^{2x}, where AA is a constant to be determined. We then compute ypy_p', ypy_p'', and substitute these into the original equation
step 3
After substituting, we equate coefficients to solve for AA. This gives us the particular solution yp(x)=12e2xx2y_p(x) = \frac{1}{2} e^{2x} x^2
step 4
The general solution is then y(x)=yc(x)+yp(x)=c2e2xx+c1e2x+12e2xx2y(x) = y_c(x) + y_p(x) = c_2 e^{2x} x + c_1 e^{2x} + \frac{1}{2} e^{2x} x^2
step 5
To find the particular solution at x=0x = 0, we evaluate y(0)=c2(0)+c1(1)+0=c1y(0) = c_2(0) + c_1(1) + 0 = c_1. Since all values of yy are solutions, we conclude that y(0)=0y(0) = 0 gives us c1=0c_1 = 0
Answer
The general solution is y(x)=c2e2xx+12e2xx2y(x) = c_2 e^{2x} x + \frac{1}{2} e^{2x} x^2 with c1=0c_1 = 0.
Key Concept
The method of undetermined coefficients is used to find particular solutions to non-homogeneous linear differential equations.
Explanation
The solution combines the complementary and particular solutions, and we find specific constants based on initial conditions or evaluations.

Not the question you are looking for? Ask here!

Enter question by text

Enter question by image

Unlock Smarter Learning with AskSia Super!

Join Super, our all-in-one AI solution that can greatly improve your learning efficiency.

30% higher accuracy than GPT-4o
Entire learning journey support
The most student-friendly features
Study Other Question