find the value of linear differential equation x. dy/dx+y=x cube.y (power six)
Answers
Step-by-step explanation:
Given--->
-----------
linear differential equation as follows
dy
x ---- + y =x³y^6
dx
To find--->
------------
solution of given differential equation
solution ---->
--------------
formulee used in solving -->
-----------------------------------------
1.
d d d
---------(u v) =u -----(v) + v -------(u)
dx dx dx
2.
solution of linear differential equation
dv
----- +p V = q
dx
where p and q are functions of x only
then
integration p integrating function = e
now solution is
v (I. F.)=integration {(I. F. ) q} dx + c
3.
logx^p
e = p
now returning to original problem
dy
x ----- + y =x ^3 y^6
dx
dividing whole equation by xy^6
x dy y x^3 y^6
----- ------ + --------- = -----------
x y^6 dx x y^6 x y^6
1 dy 1 1
-------- ------ + -------- -------- =x^2
y^6 dx x y^5
now let
1
-------- = v
y^5
y^(-5) = v
differentiating with respect to x
dy dv
-5 y^(-6) ----- = ------
dx dx
1 dy 1 dv
-------- ------- =- ------- -------
y^6 dx 5 dx
now putting in differential equation
1 dv 1
- ------- ------ + ------ v = x^2
5 dx x
multiplying by (-5) in whole equation
dv 5
------ +(- ------)v = -5x^2
dx x
5
here p=- ( ------) ,q =-5x^2
x
5
integration of (- -------)
x
I. F. =e
-5logx logx^(-5)
= e = e
=x^(-5)
now solution is
vx^(-5)= integration of (-5) x^2 x^(-5) dx
+c
1
--------------= integration (-5) x^(-3) dx + c
x^5y^5
x(-3+1)
= (-5) -------------- + c
(-3+1)
x^(-2)
=-5 --------------- + c
-2
1 5
------------ =------------ + c
x^5y^5 2x^2
hope it helps you
Thanks