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The Integrating Factor of the differential equation dydx-y=2x2 is ______. - Mathematics

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Question

The Integrating Factor of the differential equation `dy/dx - y = 2x^2` is ______.

Options

  • e-x

  • e-y

  • `1/x`

  • x

MCQ
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Solution

The Integrating Factor of the differential equation `dy/dx - y = 2x^2` is `underline(1/x)`

Explanation:

The differential equation is

`x dy/dx - y = 2x^2`

or `dy/dx - 1/x y = 2x`

Here `P = - 1/x, Q = 2x`

∴ `∫ P  dx =int - 1/x` dx

=` - log x = log  1/x`

⇒ `I.F. = e^(int P dx)`

`= e^(log 1//x) = 1/x`

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Chapter 9: Differential Equations - Exercise 9.6 [Page 414]

APPEARS IN

NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 9 Differential Equations
Exercise 9.6 | Q 18 | Page 414

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