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Verify that Y = Cx + 2c2 is a Solution of the Differential Equation 2 ( D Y D X ) 2 + X D Y D X − Y = 0 .

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Question

Verify that y = cx + 2c2 is a solution of the differential equation 

\[2 \left( \frac{dy}{dx} \right)^2 + x\frac{dy}{dx} - y = 0\].
Sum
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Solution

We have,
\[y = cx + 2 c^2..............(1)\]
Differentiating both sides of (1) with respect to x, we get

\[\frac{dy}{dx} = c...........(2)\]
Now,
\[2 \left( \frac{dy}{dx} \right)^2 + x\frac{dy}{dx} - y\]
\[ = 2 c^2 + cx - cx - 2 c^2 = 0 ...........\left[\text{Using }\left( 1 \right)\text{ and }\left( 2 \right) \right]\]
\[ \Rightarrow 2 \left( \frac{dy}{dx} \right)^2 + x\frac{dy}{dx} - y = 0\]
Hence, the given function is the solution to the given differential equation.
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Chapter 21: Differential Equations - Exercise 22.03 [Page 25]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 21 Differential Equations
Exercise 22.03 | Q 13 | Page 25

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