हिंदी

(Sin X + Cos X) Dy + (Cos X − Sin X) Dx = 0

Advertisements
Advertisements

प्रश्न

(sin x + cos x) dy + (cos x − sin x) dx = 0

Advertisements

उत्तर

We have, 
\[\left( \sin x + \cos x \right)dy + \left( \cos x - \sin x \right)dx = 0\]
\[ \Rightarrow dy = - \left( \frac{\cos x - \sin x}{\sin x + \cos x} \right)dx\]
Integrating both sides, we get
\[\int dy = - \int\left( \frac{\cos x - \sin x}{\sin x + \cos x} \right)dx\]
\[ \Rightarrow y = - \int\left( \frac{\cos x - \sin x}{\sin x + \cos x} \right)dx\]
\[\text{ Putting }\sin x + \cos x = t\]
\[ \Rightarrow \left( \cos x - \sin x \right) dx = dt\]
\[ \therefore y = - \int\frac{dt}{t}\]
\[ \Rightarrow y = - \log\left| t \right| + C\]
\[ \Rightarrow y = - \log\left| \sin x + \cos x \right| + C\]
\[ \Rightarrow y + \log\left| \sin x + \cos x \right| = C\]
\[\text{ Hence, }y + \log\left| \sin x + \cos x \right| =\text{ C is the solution to the given differential equation }.\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 21: Differential Equations - Exercise 22.05 [पृष्ठ ३४]

APPEARS IN

आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 21 Differential Equations
Exercise 22.05 | Q 11 | पृष्ठ ३४

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

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


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

Verify that \[y = e^{m \cos^{- 1} x}\] satisfies the differential equation \[\left( 1 - x^2 \right)\frac{d^2 y}{d x^2} - x\frac{dy}{dx} - m^2 y = 0\]


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

\[\cos x\frac{dy}{dx} - \cos 2x = \cos 3x\]

\[\frac{dy}{dx} = x \log x\]

\[\left( x - 1 \right)\frac{dy}{dx} = 2 xy\]

\[5\frac{dy}{dx} = e^x y^4\]

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

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


Solve the following differential equation: 
(xy2 + 2x) dx + (x2 y + 2y) dy = 0


Solve the following differential equation:
\[\text{ cosec }x \log y \frac{dy}{dx} + x^2 y^2 = 0\]


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

Solve the differential equation \[\left( 1 + x^2 \right)\frac{dy}{dx} + \left( 1 + y^2 \right) = 0\], given that y = 1, when x = 0.


Solve the differential equation \[\frac{dy}{dx} = \frac{2x\left( \log x + 1 \right)}{\sin y + y \cos y}\], given that y = 0, when x = 1.


Find the particular solution of edy/dx = x + 1, given that y = 3, when x = 0.


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

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

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

2xy dx + (x2 + 2y2) dy = 0


Solve the following initial value problem:-

\[\frac{dy}{dx} + y\cot x = 2\cos x, y\left( \frac{\pi}{2} \right) = 0\]


Solve the following initial value problem:-
\[\tan x\left( \frac{dy}{dx} \right) = 2x\tan x + x^2 - y; \tan x \neq 0\] given that y = 0 when \[x = \frac{\pi}{2}\]


Show that all curves for which the slope at any point (x, y) on it is \[\frac{x^2 + y^2}{2xy}\]  are rectangular hyperbola.


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


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`


In the following example, verify that the given function is a solution of the corresponding differential equation.

Solution D.E.
xy = log y + k y' (1 - xy) = y2

Determine the order and degree of the following differential equations.

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

Form the differential equation from the relation x2 + 4y2 = 4b2


Solve the following differential equation.

y2 dx + (xy + x2 ) dy = 0


Solve the following differential equation.

x2y dx − (x3 + y3) dy = 0


Solve the following differential equation.

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


Solve the following differential equation.

`(x + a) dy/dx = – y + a`


Select and write the correct alternative from the given option for the question 

Differential equation of the function c + 4yx = 0 is


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


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


Solve the following differential equation

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


If `y = log_2 log_2(x)` then `(dy)/(dx)` =


Solve the differential equation `dy/dx + xy = xy^2` and find the particular solution when y = 4, x = 1.


Why is the equation \[x\frac{dy}{dx} + y = 0\] classified as a differential equation?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×