English

D Y D X = 1 − X + Y − X Y

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Question

\[\frac{dy}{dx} = 1 - x + y - xy\]
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Solution

We have, 
\[\frac{dy}{dx} = 1 - x + y - xy\]
\[ \Rightarrow \frac{dy}{dx} = 1 + y - x\left( 1 + y \right)\]
\[ \Rightarrow \frac{dy}{dx} = \left( 1 + y \right)\left( 1 - x \right)\]
\[ \Rightarrow \frac{1}{1 + y}dy = \left( 1 - x \right) dx\]
Integrating both sides, we get
\[\int\frac{1}{1 + y}dy = \int\left( 1 - x \right) dx\]
\[ \Rightarrow \log \left| 1 + y \right| = x - \frac{x^2}{2} + C\]
\[\text{ Hence, }\log \left| 1 + y \right| = x - \frac{x^2}{2} +\text{ C is the required solution }.\]

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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 30 | Page 55

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