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Sin 4 X D Y D X = Cos X

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Question

\[\sin^4 x\frac{dy}{dx} = \cos x\]
Sum
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Solution

We have, 
\[ \sin^4 x\frac{dy}{dx} = \cos x\]
\[ \Rightarrow dy = \frac{\cos x}{\sin^4 x}dx\]
Integrating both sides, we get
\[ \Rightarrow \int dy = \int\frac{\cos x}{\sin^4 x}dx\]
\[ \Rightarrow y = \int\frac{\cos x}{\sin^4 x}dx\]
\[\text{ Putting }\sin x = t\]
\[ \Rightarrow \cos x dx = dt\]
\[ \therefore y = \int\frac{1}{t^4}dt\]
\[ = \frac{t^{- 3}}{- 3} + C\]
\[ = \frac{- \sin^{- 3} x}{3} + C\]
\[ = - \frac{1}{3} {cosec}^3 x + C \]
\[\text{ Hence, }y = - \frac{1}{3} {cosec}^3 x +\text{C is the solution to the given differential equation.}\]

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Chapter 21: Differential Equations - Exercise 22.05 [Page 34]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 21 Differential Equations
Exercise 22.05 | Q 14 | Page 34

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