हिंदी

Xy dydx =x2+2y2

Advertisements
Advertisements

प्रश्न

`xy dy/dx  = x^2 + 2y^2`

योग
Advertisements

उत्तर

`xy  dy/dx  = x^2 + 2y^2`

∴ `dy/dx = x^2 + (2y^2)/ (xy)`  …(i)

Put y = tx  ...(ii)

Differentiating w.r.t. x, we get

`dy/dx = t + x dt/dx`  ...(iii)

Substituting (ii) and (iii) in (i), we get

`t + x dt/dx = (x^2 + 2t^2 x^2)/ (x(tx))`

∴ `t + x dt/dx = (x^2 (1+2t^2))/(x^2t)`

∴ `x dt/dx (1+2t^2)/t - t = (1+ t^2)/t`

∴ `t/(1+t^2) dt = 1/x dx`

Integrating on both sides, we get

`1/2 int (2t)/(1+t^2)  dt = int dx/x`

∴ `1/2 log|1 + t^2| = log |x| + log |c|`

∴ log |1 + t2 | = 2 log |x| + 2log |c|

= log |x2 | + log |c2|

∴ log |1 + t2 | = log |c2 x2|

∴ 1 + t2 = c2x2

∴ `1 + y^2/x^2 = c^2x^2`

∴ x2 + y2 = c2 x4

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Differential Equation and Applications - Miscellaneous Exercise 8 [पृष्ठ १७३]

APPEARS IN

बालभारती Mathematics and Statistics 1 (Commerce) [English] Standard 12 Maharashtra State Board
अध्याय 8 Differential Equation and Applications
Miscellaneous Exercise 8 | Q 4.13 | पृष्ठ १७३

संबंधित प्रश्न

Prove that:

`int_0^(2a)f(x)dx = int_0^af(x)dx + int_0^af(2a - x)dx`


Assume that a rain drop evaporates at a rate proportional to its surface area. Form a differential equation involving the rate of change of the radius of the rain drop.

 

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

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

Verify that y = log \[\left( x + \sqrt{x^2 + a^2} \right)^2\]  satisfies the differential equation \[\left( a^2 + x^2 \right)\frac{d^2 y}{d x^2} + x\frac{dy}{dx} = 0\]


For the following differential equation verify that the accompanying function is a solution:

Differential equation Function
\[x^3 \frac{d^2 y}{d x^2} = 1\]
\[y = ax + b + \frac{1}{2x}\]

\[\sqrt{a + x} dy + x\ dx = 0\]

\[x\frac{dy}{dx} + \cot y = 0\]

Solve the following differential equation:
\[y\left( 1 - x^2 \right)\frac{dy}{dx} = x\left( 1 + y^2 \right)\]

 


Find the particular solution of the differential equation \[\frac{dy}{dx} = - 4x y^2\]  given that y = 1, when x = 0.


Find the particular solution of the differential equation
(1 – y2) (1 + log x) dx + 2xy dy = 0, given that y = 0 when x = 1.


\[\frac{dy}{dx} = \frac{\left( x - y \right) + 3}{2\left( x - y \right) + 5}\]

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

\[\frac{dy}{dx} = \frac{x}{2y + x}\]

(x + 2y) dx − (2x − y) dy = 0


Solve the following initial value problem:-

\[\frac{dy}{dx} + 2y \tan x = \sin x; y = 0\text{ when }x = \frac{\pi}{3}\]


Find the equation of the curve which passes through the origin and has the slope x + 3y− 1 at any point (x, y) on it.


Write the differential equation obtained eliminating the arbitrary constant C in the equation xy = C2.


The differential equation
\[\frac{dy}{dx} + Py = Q y^n , n > 2\] can be reduced to linear form by substituting


y2 dx + (x2 − xy + y2) dy = 0


Verify that the function y = e−3x is a solution of the differential equation \[\frac{d^2 y}{d x^2} + \frac{dy}{dx} - 6y = 0.\]


In the following verify that the given functions (explicit or implicit) is a solution of the corresponding differential equation:-

`y=sqrt(a^2-x^2)`              `x+y(dy/dx)=0`


Solve the following differential equation.

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


Solve the following differential equation.

`(x + y) dy/dx = 1`


Solve the following differential equation.

`dy/dx + 2xy = x`


Solve the differential equation:

`e^(dy/dx) = x`


Solve the following differential equation y log y = `(log  y - x) ("d"y)/("d"x)`


Solve the following differential equation y2dx + (xy + x2) dy = 0


Solve: ydx – xdy = x2ydx.


lf the straight lines `ax + by + p` = 0 and `x cos alpha + y sin alpha = p` are inclined at an angle π/4 and concurrent with the straight line `x sin alpha - y cos alpha` = 0, then the value of `a^2 + b^2` is


Solve the differential equation

`y (dy)/(dx) + x` = 0


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×