मराठी

D Y D X = 2 X Y , Y ( 0 ) = 1

Advertisements
Advertisements

प्रश्न

\[\frac{dy}{dx} = 2xy, y\left( 0 \right) = 1\]
Advertisements

उत्तर

\[ \frac{dy}{dx} = 2xy, y\left( 0 \right) = 1\]
\[ \Rightarrow \frac{1}{y}dy = 2x dx\]
Integrating both sides, we get 
\[\int\frac{1}{y}dy = \int2x dx\]
\[\log \left| y \right| = x^2 + C . . . . . (1)\]
\[\text{We know that at }x = 0, y = 1 . \]
Substituting the values of x and y in (1), we get
\[0 = 0 + C\]
\[ \Rightarrow C = 0\]
Substituting the value of C in (1), we get 
\[\log \left| y \right| = x^2 \]
\[ \Rightarrow y = e^{x^2} \]
\[\text{ Hence, }y = e^{x^2}\text{ is the required solution }. \]

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 21: Differential Equations - Exercise 22.07 [पृष्ठ ५६]

APPEARS IN

आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 21 Differential Equations
Exercise 22.07 | Q 45.5 | पृष्ठ ५६

व्हिडिओ ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्‍न

\[\frac{d^3 x}{d t^3} + \frac{d^2 x}{d t^2} + \left( \frac{dx}{dt} \right)^2 = e^t\]

\[\sqrt{1 + \left( \frac{dy}{dx} \right)^2} = \left( c\frac{d^2 y}{d x^2} \right)^{1/3}\]

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

\[\sqrt[3]{\frac{d^2 y}{d x^2}} = \sqrt{\frac{dy}{dx}}\]

Show that the function y = A cos x + B sin x is a solution of the differential equation \[\frac{d^2 y}{d x^2} + y = 0\]


Show that Ax2 + By2 = 1 is a solution of the differential equation x \[\left\{ y\frac{d^2 y}{d x^2} + \left( \frac{dy}{dx} \right)^2 \right\} = y\frac{dy}{dx}\]

 


Verify that y = − x − 1 is a solution of the differential equation (y − x) dy − (y2 − x2) dx = 0.


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


Show that y = e−x + ax + b is solution of the differential equation\[e^x \frac{d^2 y}{d x^2} = 1\]

 


\[\sin^4 x\frac{dy}{dx} = \cos x\]

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

\[\frac{dy}{dx} = \sin^2 y\]

\[\frac{dy}{dx} = \left( e^x + 1 \right) y\]

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


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

 


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

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

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

 


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.


Find the equation of the curve which passes through the point (1, 2) and the distance between the foot of the ordinate of the point of contact and the point of intersection of the tangent with x-axis is twice the abscissa of the point of contact.


The normal to a given curve at each point (x, y) on the curve passes through the point (3, 0). If the curve contains the point (3, 4), find its equation.


The integrating factor of the differential equation (x log x)
\[\frac{dy}{dx} + y = 2 \log x\], is given by


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


Solve the following differential equation : \[\left( \sqrt{1 + x^2 + y^2 + x^2 y^2} \right) dx + xy \ dy = 0\].


y2 dx + (x2 − xy + y2) dy = 0


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

y = ex + 1            y'' − y' = 0


Form the differential equation of the family of circles having centre on y-axis and radius 3 unit.


If a + ib = `("x" + "iy")/("x" - "iy"),` prove that `"a"^2 +"b"^2 = 1` and `"b"/"a" = (2"xy")/("x"^2 - "y"^2)`


Determine the order and degree of the following differential equations.

Solution D.E
y = aex + be−x `(d^2y)/dx^2= 1`

Solve the following differential equation.

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


 `dy/dx = log x`


Solve the differential equation `("d"y)/("d"x) + y` = e−x 


Solve the differential equation (x2 – yx2)dy + (y2 + xy2)dx = 0


Solve the following differential equation

`yx ("d"y)/("d"x)` = x2 + 2y2 


Solve the following differential equation

`y log y ("d"x)/("d"y) + x` = log y


Solve the following differential equation `("d"y)/("d"x)` = cos(x + y)

Solution: `("d"y)/("d"x)` = cos(x + y)    ......(1)

Put `square`

∴ `1 + ("d"y)/("d"x) = "dv"/("d"x)`

∴ `("d"y)/("d"x) = "dv"/("d"x) - 1`

∴ (1) becomes `"dv"/("d"x) - 1` = cos v

∴ `"dv"/("d"x)` = 1 + cos v

∴ `square` dv = dx

Integrating, we get

`int 1/(1 + cos "v")  "d"v = int  "d"x`

∴ `int 1/(2cos^2 ("v"/2))  "dv" = int  "d"x`

∴ `1/2 int square  "dv" = int  "d"x`

∴ `1/2* (tan("v"/2))/(1/2)` = x + c

∴ `square` = x + c


Solve: `("d"y)/("d"x) = cos(x + y) + sin(x + y)`. [Hint: Substitute x + y = z]


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×