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Solve: dydx+2xy = x2 - Mathematics and Statistics

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Question

Solve: `("d"y)/("d"x) + 2/xy` = x2 

Sum
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Solution

`("d"y)/("d"x) + 2/xy` = x2 

The given equation is of the form

`("d"y)/("d"x) + "P"y` = Q.

where P = `2/x` and Q = x2

∴ I.F. = `"e"^(int^("Pd"x))`

= `"e"^(int2/x)  "d"x`

= `"e"^(2logx)`

= `"e"^(log x^2)`

= x2

∴ Solution of the given equation is

`y("I"."F".) = int"Q"("I.""F.")  "d"x + "c"_1`

∴ `y * x^2 = intx^2 * x^2  "d"x + "c"_1`

∴ `yx^2 = intx^4  "d"x + "c"_1`

∴ yx2 = `x^5/5 + "c"_1`

∴ 5x2y = x5 + c, where c = 5c1 

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Chapter 1.8: Differential Equation and Applications - Q.4

APPEARS IN

SCERT Maharashtra Mathematics and Statistics (Commerce) [English] 12 Standard HSC
Chapter 1.8 Differential Equation and Applications
Q.4 | Q 10
SCERT Maharashtra Mathematics and Statistics (Arts and Science) [English] 12 Standard HSC
Chapter 2.6 Differential Equations
Attempt the following questions II | Q 10

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