हिंदी

Solve dydxx2dydx-xy=1+cos(yx), x ≠ 0 and x = 1, y = π2 - Mathematics

Advertisements
Advertisements

प्रश्न

Solve `x^2 "dy"/"dx" - xy = 1 + cos(y/x)`, x ≠ 0 and x = 1, y = `pi/2`

योग
Advertisements

उत्तर

Given equation can be written as

`x^2 "dy"/"dx" - xy = 2cos^2 (y/2x)`, x ≠ 0.

⇒ `(x^2 "dy"/"dx" - xy)/(2cos^2 (y/(2x))` = 1

⇒ `sec^2 (y/(2x))/2 [x^2 "dy"/"dx" - xy]` = 1

Dividing both sides by x3, we get

`sec^2(y/(2x))/2 [(x "dy"/"dx" - y)/x^2] = 1/x^3`

⇒ `"d"/"dx"[tan(y/(2x))] = 1/x^3`

Integrating both sides, we get

`tan(y/(2x)) = (-1)/(2x^2) + "k"`

Substituting x = 1, y = `pi/2`, we get

k = `3/2`

Therefore, `tan(y/(2x)) = -1/(2x^2) + 3/2` is the required solution.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 9: Differential Equations - Solved Examples [पृष्ठ १८५]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 9 Differential Equations
Solved Examples | Q 10 | पृष्ठ १८५

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

Hence, the given function is the solution to the given differential equation. \[\frac{c - x}{1 + cx}\] is a solution of the differential equation \[(1+x^2)\frac{dy}{dx}+(1+y^2)=0\].


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

\[\frac{dy}{dx} + 2x = e^{3x}\]

\[\frac{dy}{dx} = \frac{1 - \cos x}{1 + \cos x}\]

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


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

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

(y + xy) dx + (x − xy2) dy = 0


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

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

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.


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

x2 dy + y (x + y) dx = 0


\[\left[ x\sqrt{x^2 + y^2} - y^2 \right] dx + xy\ dy = 0\]

Solve the following initial value problem:-
\[x\frac{dy}{dx} - y = \log x, y\left( 1 \right) = 0\]


If the marginal cost of manufacturing a certain item is given by C' (x) = \[\frac{dC}{dx}\] = 2 + 0.15 x. Find the total cost function C (x), given that C (0) = 100.

 

The decay rate of radium at any time t is proportional to its mass at that time. Find the time when the mass will be halved of its initial mass.


Find the equation of the curve passing through the point \[\left( 1, \frac{\pi}{4} \right)\]  and tangent at any point of which makes an angle tan−1  \[\left( \frac{y}{x} - \cos^2 \frac{y}{x} \right)\] with x-axis.


The tangent at any point (x, y) of a curve makes an angle tan−1(2x + 3y) with x-axis. Find the equation of the curve if it passes through (1, 2).


Find the solution of the differential equation
\[x\sqrt{1 + y^2}dx + y\sqrt{1 + x^2}dy = 0\]


The equation of the curve whose slope is given by \[\frac{dy}{dx} = \frac{2y}{x}; x > 0, y > 0\] and which passes through the point (1, 1) is


The solution of the differential equation \[\frac{dy}{dx} = \frac{ax + g}{by + f}\] represents a circle when


The integrating factor of the differential equation \[x\frac{dy}{dx} - y = 2 x^2\]


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


Find the coordinates of the centre, foci and equation of directrix of the hyperbola x2 – 3y2 – 4x = 8.


Determine the order and degree of the following differential equations.

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

Find the differential equation whose general solution is

x3 + y3 = 35ax.


For each of the following differential equations find the particular solution.

(x − y2 x) dx − (y + x2 y) dy = 0, when x = 2, y = 0


Solve the following differential equation.

x2y dx − (x3 + y3) dy = 0


Solve the following differential equation.

(x2 − y2 ) dx + 2xy dy = 0


Solve the following differential equation.

`xy  dy/dx = x^2 + 2y^2`


Solve the following differential equation.

`(x + a) dy/dx = – y + a`


Solve the following differential equation.

dr + (2r)dθ= 8dθ


Choose the correct alternative.

The solution of `x dy/dx = y` log y is


Choose the correct alternative.

Bacteria increases at the rate proportional to the number present. If the original number M doubles in 3 hours, then the number of bacteria will be 4M in


An appropriate substitution to solve the differential equation `"dx"/"dy" = (x^2 log(x/y) - x^2)/(xy log(x/y))` is ______.


Solution of `x("d"y)/("d"x) = y + x tan  y/x` is `sin(y/x)` = cx


The differential equation of all non horizontal lines in a plane is `("d"^2x)/("d"y^2)` = 0


Solve the differential equation

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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×