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Differential Equation X D Y D X = 1 , Y ( 1 ) = 0 Function Y = Log X - Mathematics

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Question

Differential equation \[x\frac{dy}{dx} = 1, y\left( 1 \right) = 0\]

Function y = log x

Sum

Solution

We have,

\[y = \log x...........(1)\]

Differentiating both sides of (1) with respect to x, we get

\[\frac{dy}{dx} = \frac{1}{x}\]

or,

\[x\frac{dy}{dx} = 1\]

It is the given differential equation.

Thus, \[y = \log x\]  satisfies the given differential equation.

Hence, it is a solution.

Also, when \[x = 1, y = \log 1 = 0, i.e., y\left( 1 \right) = 0\]

Hence, \[y = \log x\] is the solution to the given initial value problem.

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Chapter 22: Differential Equations - Exercise 22.04 [Page 28]

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RD Sharma Mathematics [English] Class 12
Chapter 22 Differential Equations
Exercise 22.04 | Q 1 | Page 28

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