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Verify that the Function Y = E−3x is a Solution of the Differential Equation D 2 Y D X 2 + D Y D X − 6 Y = 0. - Mathematics

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प्रश्न

Verify that the function y = e−3x is a solution of the differential equation \[\frac{d^2 y}{d x^2} + \frac{dy}{dx} - 6y = 0.\]

योग

उत्तर

We have
\[\frac{d^2 y}{d x^2} + \frac{dy}{dx} - 6y = 0 . . . . . \left( 1 \right)\]
\[Now, \]
\[y = e^{- 3x} \]
\[ \Rightarrow \frac{dy}{dx} = - 3 e^{- 3x} \]
\[\Rightarrow\frac{d^2y}{dx^2}=9e^{-3x}\]

\[\text{Putting the values of }\frac{d^2 y}{d x^2}, \frac{dy}{dx}\text{ and y in (1), we get}\]

\[LHS = 9 e^{- 3x} - 3 e^{- 3x} - 6 e^{- 3x} \]
\[ = 0\]
\[ = RHS\]

Thus, y = e−3x is the solution of the given differential equation.

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अध्याय 22: Differential Equations - Revision Exercise [पृष्ठ १४४]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 22 Differential Equations
Revision Exercise | Q 2 | पृष्ठ १४४

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