मराठी

Show that the given differential equation is homogeneous and solve them. x2dydx =x2-2y2+xy

Advertisements
Advertisements

प्रश्न

Show that the given differential equation is homogeneous and solve them.

`x^2 dy/dx = x^2 - 2y^2 + xy`

बेरीज
Advertisements

उत्तर

Given `x^2 dy/dx = x^2 - 2y^2 + xy`

⇒ `dy/dx = (x^2 - 2y^2 + xy)/x^2`

`= 1 - 2 (y^2/x) + y/x`                ....(1)

Since R.H.S. is of the form `g(y/x)`, and so it is a homogeneous function of degree zero.

Therefore equation (1) is a homogeneous differential equation.

∴ put y = vx

⇒ `dy/dx = v.1 + x (dv)/dx`

Substituting these values of y and `dy/dx` in the given equation, we get

`v + x (dv)/dx = 1 - 2 v^2 + v`

⇒ `x (dv)/dx = 1 - 2v^2`

⇒ `1/x dx = 1/ (1 - 2v^2)  dv`

On integration, we get

`log |x| = int 1/ (1 - 2v^2) dv + C`

⇒ `log |x| = 1/2 int (dv)/ ((1/ sqrt2)^2 - v^2) + C`

⇒ `log |x| = 1/2 * 1/ (2* (1/sqrt2)) log |((1/sqrt2)+v)/((1/sqrt2) - v)| + C`

⇒ `log |x| = 1/(2sqrt2) log |(1 + sqrt(2v))/(1 - sqrt(2v))| + C`

⇒ `log |x| = 1/ (2 sqrt2) log |(1 + sqrt2* (y/x))/(1 - sqrt2 * (y/x))| + C`

⇒ `log |x| = 1/ (2sqrt2) log | (x + sqrt(2y))/(x - sqrt(2y))| + C`

Where C is an arbitrary constant

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 9: Differential Equations - Exercise 9.5 [पृष्ठ ४०६]

APPEARS IN

एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
पाठ 9 Differential Equations
Exercise 9.5 | Q 5 | पृष्ठ ४०६

संबंधित प्रश्‍न

Find the particular solution of the differential equation:

2y ex/y dx + (y - 2x ex/y) dy = 0 given that x = 0 when y = 1.


Show that the given differential equation is homogeneous and solve them.

(x2 + xy) dy = (x2 + y2) dx


Show that the given differential equation is homogeneous and solve them.

`x dy/dx - y +  x sin (y/x) = 0`


For the differential equation find a particular solution satisfying the given condition:

(x + y) dy + (x – y) dx = 0; y = 1 when x = 1


For the differential equation find a particular solution satisfying the given condition:

x2 dy + (xy + y2) dx = 0; y = 1 when x = 1


For the differential equation find a particular solution satisfying the given condition:

`2xy + y^2 - 2x^2  dy/dx = 0; y = 2`   when x  = 1


Which of the following is a homogeneous differential equation?


\[\left( x^2 + y^2 \right)\frac{dy}{dx} = 8 x^2 - 3xy + 2 y^2\]

\[x\frac{dy}{dx} - y = 2\sqrt{y^2 - x^2}\]

\[x \cos\left( \frac{y}{x} \right) \cdot \left( y dx + x dy \right) = y \sin\left( \frac{y}{x} \right) \cdot \left( x dy - y dx \right)\]

\[\left( x - y \right)\frac{dy}{dx} = x + 2y\]

\[x\frac{dy}{dx} - y + x \sin\left( \frac{y}{x} \right) = 0\]

\[y dx + \left\{ x \log\left( \frac{y}{x} \right) \right\} dy - 2x dy = 0\]

Solve the following initial value problem:
(y4 − 2x3 y) dx + (x4 − 2xy3) dy = 0, y (1) = 1


Show that the family of curves for which \[\frac{dy}{dx} = \frac{x^2 + y^2}{2xy}\], is given by \[x^2 - y^2 = Cx\]


Solve the following differential equation:

`(1 + 2"e"^("x"/"y")) + 2"e"^("x"/"y")(1 - "x"/"y") "dy"/"dx" = 0`


Solve the following differential equation:

y2 dx + (xy + x2)dy = 0


Solve the following differential equation:

`"dy"/"dx" + ("x" - "2y")/("2x" - "y") = 0`


Solve the following differential equation:

`(1 + "e"^("x"/"y"))"dx" + "e"^("x"/"y")(1 - "x"/"y")"dy" = 0`


Solve the following differential equation:

`x^2.  dy/dx = x^2 + xy + y^2`


Solve the following differential equation:

(9x + 5y) dy + (15x + 11y)dx = 0


Which of the following is not a homogeneous function of x and y.


F(x, y) = `(ycos(y/x) + x)/(xcos(y/x))` is not a homogeneous function.


Solve : `x^2 "dy"/"dx"` = x2 + xy + y2.


A homogeneous differential equation of the `(dx)/(dy) = h(x/y)` can be solved by making the substitution.


The differential equation y' = `y/(x + sqrt(xy))` has general solution given by:

(where C is a constant of integration)


The solution of the differential equation y2 dx + (x2 − xy + y2)dy = 0 is ______.


After using \[y=vx\] and writing the right-hand side as \[g(v)\], which separable form is obtained?


For the substitution \[x=vy\], which differentiated form is correct?


For \[F(x,y)=\frac{y\cos\left(\frac{y}{x}\right)+x}{x\cos\left(\frac{y}{x}\right)}\], what is \[F(\lambda x,\lambda y)\]?


After putting \[y=vx\] in \[\frac{dy}{dx}=\frac{y\cos\left(\frac{y}{x}\right)+x}{x\cos\left(\frac{y}{x}\right)}\], which equation results?


From \[v+x\frac{dv}{dx}=\frac{v\cos v+1}{\cos v}\], what is \[x\frac{dv}{dx}\]?


Which separable equation follows from \[x\frac{dv}{dx}=\frac{1}{\cos v}\]?


Which final answer results after replacing \[v=\frac{y}{x}\] in \[\sin v=\ln|Cx|\]?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×