Solve ( D 3 + 1 ) 2 Y = 0 - Applied Mathematics 2

Sum

Solve (D^3+1)^2y=0

Solution

(D^3+1)^2y=0

For complementary solution,
f(D) = 0
therefore(D^3+1)^2=0

therefore(D^3+1)=0

Roots are : "D"=-1,1/2+isqrt3/2,1/2-isqrt3/2  .. for two times

Roots of given diff. eqn are real and complex.
The general solution of given diff. eqn is given by ,

y_g=y_c=(c_1+xc_2)e^(-x)+e^(x/2)[(c^3+xc_4)cosx+(c_5+xc_6)sinx

Concept: Linear Differential Equation with Constant Coefficient‐ Complementary Function
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