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Nonhomogeneous equations
Driving forces: homogeneous solution plus a particular solution.
With a forcing term on the right, the general solution is the homogeneous solution plus any one particular solution. Undetermined coefficients guesses the particular solution in the shape of the forcing (exponential, polynomial, sinusoid); variation of parameters handles the rest.
ਕੰਮ ਉਦਾਹਰਨ: y'' - 3y' + 2y = e^x
Solve y'' - 3y' + 2y = e^x
ਕਦਮ ਦਰ ਕਦਮ
- 2 y{\left(x \right)} - 3 \frac{d}{d x} y{\left(x \right)} + \frac{d^{2}}{d x^{2}} y{\left(x \right)} = e^{x}
The differential equation.
- \text{order } 2
Order 2: the highest derivative present.
- \text{Undetermined coefficients}
Solve the homogeneous part from the characteristic equation, then guess a particular solution shaped like the right-hand side.
- r^{2} - 3 r + 2 = 0
Characteristic equation of the homogeneous part (substitute y = e^{rx}).
- r = 2,\ r = 1
Its roots.
- y{\left(x \right)} = \left(C_{1} + C_{2} e^{x} - x\right) e^{x}
General solution (C₁, C₂ … are arbitrary constants).
- \checkmark
Verified: substituting the solution back into the equation gives 0.
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ਹੋਰ ਵਿੱਚ Differential Equations
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