Given equation is y'+xy=xy^(-1)
An equation of the form y'+Py=Qy^n
is called as the Bernoulli equation .
so, to proceed to solve this equation we have to transform the equation into a linear equation form of first order as follows
=> y' (y^-n) +P y^(1-n)=Q
let u= y^(1-n)
=> (1-n)y^(-n)y'=u'
=> y^(-n)y' = (u')/(1-n)
so ,
y' (y^-n) +P y^(1-n)=Q
=> (u')/(1-n) +P u =Q
so this equation is now of the linear form of first order
Now,
From this equation ,
y'+xy=xy^(-1)
and
y'+Py=Qy^n
on comparing we get
P=x , Q=x , n=-1
so the linear form of first order of the equation y'+xy=xy^(-1) is given as
=> (u')/(1-n) +P u =Q where u= y^(1-n) =y^2
=> (u')/(1-(-1)) +(x)u =x
=> (u')/2 +xu=x
=> u'+2xu = 2x
so this linear equation is of the form
u' + pu=q
p=2x , q=2x
so I.F (integrating factor ) = e^(int p dx) = e^(int 2x dx) = e^2(x^2)/2 = e^(x^2)
and the general solution is given as
u (I.F)=int q * (I.F) dx +c
=> u(e^(x^2))= int (2x) *(e^(x^2)) dx+c
=> u(e^(x^2))= int (e^(x^2)) 2xdx+c
let us first solve
int e^(x^2) 2xdx
so , let t =x^2
dt = 2xdx
int e^(x^2) 2xdx = int e^(t) dt = e^t = e^(x^2)
so now => ue^(x^2)= e^(x^2)+c
=>u=((e^(x^2))+c)/(e^(x^2))
= 1 +ce^(-x^2)
but
u=y^2 ,so
y^2=(1 +ce^(-x^2))
y= sqrt (1 +ce^(-x^2))
is the general solution.
Thursday, August 30, 2012
y' + xy = xy^-1 Solve the Bernoulli differential equation.
Subscribe to:
Post Comments (Atom)
Summarize the major research findings of "Toward an experimental ecology of human development."
Based on findings of prior research, the author, Bronfenbrenner proposes that methods for natural observation research have been applied in ...
-
Find the indefinite integral $\displaystyle \int \sec^4 \left( \frac{x}{2} \right) dx$. Illustrate by graphing both the integrand and its an...
-
Determine $\displaystyle \frac{dy}{dx}$ of $y^5 + x^2y^3 = 1 + x^4 y$ by Implicit Differentiation. $\displaystyle \frac{d}{dx}(y^5) + ...
-
Determine the area of the region bounded by the hyperbola $9x^2 - 4y^2 = 36$ and the line $ x= 3$ By using vertical strips, Si...
-
Find the integral $\displaystyle \int^1_0 \frac{1}{\sqrt{16 t^2 + 1}} dt$ If we let $u = 4t$, then $du = 4dt$, so $\displaystyle dt = \frac{...
-
Determine the integral $\displaystyle \int \frac{\sin^3 (\sqrt{x})}{\sqrt{x}} dx$ Let $u = \sqrt{x}$, then $\displaystyle du = \frac{1}{2 \s...
-
Gertrude's comment "The lady protests too much, methinks" in act 3, scene 2, of Shakespeare's Hamlet exposes her own guilt...
-
Given y=cos(2x), y=0 x=0,x=pi/4 so the solid of revolution about x-axis is given as V = pi * int _a ^b [R(x)^2 -r(x)^2] dx here R(x) =cos(2x...
No comments:
Post a Comment