Pls solve (D^3-3D+2)y=e^5x
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Ptolemy is wrong because the homogeneous equation has the general solution y = Ae^(-x) + Be^(-2x). Because the nonhomogeneous function is e^(e^x), we cannot use the method of undetermined coefficients; we must use variation of parameters.
We seek functions E(x) and F(x) such that
E(x)e^(-x) + F(x)e^(-2x) is a particular solution of the nonhomogeneous equation. We find that the derivatives of E and F must satisfy the conditions
E'(x)e^(-x) + F'(x)e^(-2x) = 0
-E'(x)e^(-x) - 2F'(x)e^(-2x) = e^(e^x).
We simplify these conditions by multiplying through by e^x:
E' + F'e^(-x) = 0
-E' - 2F'e^(-x) = e^(e^x)
We find that E'(x) = e^(e^x + x) and F'(x) = - e^(e^x + 2x). Taking the antiderivatives, we find E(x) = e^(e^x)
and F(x) = e^(e^x) - (e^x)*e^(e^x).
Now E*e^(-x) + F*e^(-2x) = e^(e^x - 2x); you can verify that this is a particular solution. The general solution is
y = Ae^(-x) + Be^(-2x) + e^(e^x - 2x).
We seek functions E(x) and F(x) such that
E(x)e^(-x) + F(x)e^(-2x) is a particular solution of the nonhomogeneous equation. We find that the derivatives of E and F must satisfy the conditions
E'(x)e^(-x) + F'(x)e^(-2x) = 0
-E'(x)e^(-x) - 2F'(x)e^(-2x) = e^(e^x).
We simplify these conditions by multiplying through by e^x:
E' + F'e^(-x) = 0
-E' - 2F'e^(-x) = e^(e^x)
We find that E'(x) = e^(e^x + x) and F'(x) = - e^(e^x + 2x). Taking the antiderivatives, we find E(x) = e^(e^x)
and F(x) = e^(e^x) - (e^x)*e^(e^x).
Now E*e^(-x) + F*e^(-2x) = e^(e^x - 2x); you can verify that this is a particular solution. The general solution is
y = Ae^(-x) + Be^(-2x) + e^(e^x - 2x).
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Answer:
Simplifying
(D2 + -3D + 2) * y = e5x
Reorder the terms:
(2 + -3D + D2) * y = e5x
Reorder the terms for easier multiplication:
y(2 + -3D + D2) = e5x
(2 * y + -3D * y + D2 * y) = e5x
(2y + -3yD + yD2) = e5x
Solving
2y + -3yD + yD2 = e5x
Solving for variable 'y'.
Move all terms containing y to the left, all other terms to the right.
Reorder the terms:
-1e5x + 2y + -3yD + yD2 = e5x + -1e5x
Combine like terms: e5x + -1e5x = 0
-1e5x + 2y + -3yD + yD2 = 0
The solution to this equation could not be determined.
Step-by-step explanation:
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