Question #656be

1 Answer
Jul 13, 2016

y = C_1e^{lambda_1 x}+C_2e^{lambda_2 x} with
lambda_1 =-1/2 (2 + sqrt[3]) and
lambda_2=-1/2(2-sqrt(3))

Explanation:

This is a linear homogeneous differential equation with constant coefficients. For this equation, the solution has the structure

y = Ce^{lambda x}

substituting we have

(2 lambda^2+4lambda+1/2)Ce^{lambda x} = 0

but Ce^{lambda x} ne 0 so the feasible lambda's are the solutions of

2 lambda^2+4lambda+1/2=0

which have as solutions

lambda_1 =-1/2 (2 + sqrt[3]) and
lambda_2=-1/2(2-sqrt(3))

then, the general solution is

y = C_1e^{lambda_1 x}+C_2e^{lambda_2 x}