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D Y D X = E X + Y + E Y X 3

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Question

\[\frac{dy}{dx} = e^{x + y} + e^y x^3\]
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Solution

We have,
\[\frac{dy}{dx} = e^{x + y} + e^y x^3 \]
\[ \Rightarrow \frac{dy}{dx} = e^x e^y + e^y x^3 \]
\[ \Rightarrow \frac{dy}{dx} = e^y \left( e^x + x^3 \right)\]
\[ \Rightarrow \left( e^x + x^3 \right) dx = \frac{1}{e^y}dy\]
Integrating both sides, we get 
\[\int\left( e^x + x^3 \right) dx = \int\frac{1}{e^y}dy\]
\[ \Rightarrow e^x + \frac{x^4}{4} = - e^{- y} + C\]
\[ \Rightarrow e^x + e^{- y} + \frac{x^4}{4} = C\]
\[\text{ Hence, } e^x + e^{- y} + \frac{x^4}{4} =\text{ C is the required solution .} \]

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Chapter 21: Differential Equations - Exercise 22.07 [Page 55]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 21 Differential Equations
Exercise 22.07 | Q 15 | Page 55

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