InterviewSolution
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Solve: (d4 + 2d3 - 3d2 - 4d + 4) = 0 |
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Answer» (D4 + 2D3 – 3D2 – 4D + 4)y = 0 Its auxilary equation is m4 + 2m3 – 3m2 – 4m + 4 = 0 ⇒ (m – 1)(m3 + 3m2 – 4) = 0 ⇒ (m – 1)2(m2 + 4m + 4) = 0 ⇒ (m – 1)2(m + 2)2 = 0 ⇒ m = 1, 1, –2, –2. C.F. is y = (C1 + C2x)ex + (C3 + C4x)e-2x Hence, solution of given differential equation is y = (C1 + C2x)ex + (C3 + c4x)e-2x. |
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