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Sin 4 X D Y D X = Cos X - Mathematics

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प्रश्न

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

उत्तर

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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अध्याय 22: Differential Equations - Exercise 22.05 [पृष्ठ ३४]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 22 Differential Equations
Exercise 22.05 | Q 14 | पृष्ठ ३४

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