English

D Y D X = 2 E 2 X Y 2 , Y ( 0 ) = − 1 - Mathematics

Advertisements
Advertisements

Question

\[\frac{dy}{dx} = 2 e^{2x} y^2 , y\left( 0 \right) = - 1\]
Advertisements

Solution

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

shaalaa.com
  Is there an error in this question or solution?
Chapter 22: Differential Equations - Exercise 22.07 [Page 56]

APPEARS IN

RD Sharma Mathematics [English] Class 12
Chapter 22 Differential Equations
Exercise 22.07 | Q 45.3 | Page 56

Video TutorialsVIEW ALL [2]

RELATED QUESTIONS

Solve the equation for x: `sin^(-1)  5/x + sin^(-1)  12/x = π/2, x ≠ 0`


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

\[\frac{d^2 y}{d x^2} + 4y = 0\]

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

Show that y = AeBx is a solution of the differential equation

\[\frac{d^2 y}{d x^2} = \frac{1}{y} \left( \frac{dy}{dx} \right)^2\]

Verify that y2 = 4ax is a solution of the differential equation y = x \[\frac{dy}{dx} + a\frac{dx}{dy}\]


Verify that \[y = ce^{tan^{- 1}} x\]  is a solution of the differential equation \[\left( 1 + x^2 \right)\frac{d^2 y}{d x^2} + \left( 2x - 1 \right)\frac{dy}{dx} = 0\]


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

 


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

Differential equation Function
\[y = \left( \frac{dy}{dx} \right)^2\]
\[y = \frac{1}{4} \left( x \pm a \right)^2\]

Differential equation \[\frac{d^2 y}{d x^2} + y = 0, y \left( 0 \right) = 1, y' \left( 0 \right) = 1\] Function y = sin x + cos x


\[\frac{dy}{dx} = x^5 + x^2 - \frac{2}{x}, x \neq 0\]

\[\frac{dy}{dx} + \frac{1 + y^2}{y} = 0\]

xy dy = (y − 1) (x + 1) dx


\[\cos x \cos y\frac{dy}{dx} = - \sin x \sin y\]

\[\frac{dy}{dx} = y \tan x, y\left( 0 \right) = 1\]

\[\frac{dy}{dx} = \left( x + y + 1 \right)^2\]

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

Solve the following initial value problem:-

\[dy = \cos x\left( 2 - y\text{ cosec }x \right)dx\]


The population of a city increases at a rate proportional to the number of inhabitants present at any time t. If the population of the city was 200000 in 1990 and 250000 in 2000, what will be the population in 2010?


Experiments show that radium disintegrates at a rate proportional to the amount of radium present at the moment. Its half-life is 1590 years. What percentage will disappear in one year?


Write the differential equation obtained by eliminating the arbitrary constant C in the equation x2 − y2 = C2.


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


The solution of the differential equation y1 y3 = y22 is


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


Which of the following is the integrating factor of (x log x) \[\frac{dy}{dx} + y\] = 2 log x?


Integrating factor of the differential equation cos \[x\frac{dy}{dx} + y \sin x = 1\], is


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`


Choose the correct option from the given alternatives:

The solution of `1/"x" * "dy"/"dx" = tan^-1 "x"` is


Determine the order and degree of the following differential equations.

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

Solve the following differential equation.

`(x + a) dy/dx = – y + a`


y2 dx + (xy + x2)dy = 0


Solve the following differential equation `("d"y)/("d"x)` = x2y + y


The function y = ex is solution  ______ of differential equation


The solution of differential equation `x^2 ("d"^2y)/("d"x^2)` = 1 is ______


Verify y = log x + c is the solution of differential equation `x ("d"^2y)/("d"x^2) + ("d"y)/("d"x)` = 0


Solve the following differential equation

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


Integrating factor of the differential equation `x "dy"/"dx" - y` = sinx is ______.


`d/(dx)(tan^-1  (sqrt(1 + x^2) - 1)/x)` is equal to:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×