LINEAR DIFFERENTIAL 
EQUATION
Linear differential equation 
 Definition 
 Any function on multiplying by which the differential 
equation M(x,y)dx+N(x,y)dy=0 becomes a differential 
coefficient of some function of x and y is called an 
Integrating factor of the differential equation. 
 If μ [M(x,y)dx +N(x,y)dy]=0=d[f(x,y)] then μ is called 
I.F
 Case-1 
+P(x)y=Q(x) 
 Is called a first order linear differential equation. 
I.F=eP(x)dx 
 The general solution is 
Y(I.F)=
 Example-1 
The equation is 
Here P=1, Q=x 
I.F=e1dx =ex 
The solution is 
Y(I.F)= 
Yex= ex+c 
=xex-ex+c 
Y=x-1+ce-x
 Case-2 
+P(y)x=Q(y) 
 Is Linear differential equation 
I.F= 
 The general solution is 
X(I.F)=
 Example-2 
The equation is 
Here P= , Q= 
I.F=e-logy= 
The solution is 
X(I.F)= 
X =
Bernoulli’s Equation 
 Definition 
 A differential equation is 
 Case-1 
The general solution is 
yn 
v(I.F)=
x2y6 
y-5=x2 
Put v=y-5 
= -5y-6 
+ x2 
=-5x2 
Here P= , Q= 
I.F=e-5logx=x-5 
The solution is 
v(I.F)= 
VX-5= dx +c 
VX-5= dx +c 
= x2 + c Y-5= x3 +cx5
 Case-2 
The general solution is 
v(I.F)=
Linear differential equation

Linear differential equation

  • 1.
  • 2.
    Linear differential equation  Definition  Any function on multiplying by which the differential equation M(x,y)dx+N(x,y)dy=0 becomes a differential coefficient of some function of x and y is called an Integrating factor of the differential equation.  If μ [M(x,y)dx +N(x,y)dy]=0=d[f(x,y)] then μ is called I.F
  • 3.
     Case-1 +P(x)y=Q(x)  Is called a first order linear differential equation. I.F=eP(x)dx  The general solution is Y(I.F)=
  • 4.
     Example-1 Theequation is Here P=1, Q=x I.F=e1dx =ex The solution is Y(I.F)= Yex= ex+c =xex-ex+c Y=x-1+ce-x
  • 5.
     Case-2 +P(y)x=Q(y)  Is Linear differential equation I.F=  The general solution is X(I.F)=
  • 6.
     Example-2 Theequation is Here P= , Q= I.F=e-logy= The solution is X(I.F)= X =
  • 7.
    Bernoulli’s Equation Definition  A differential equation is  Case-1 The general solution is yn v(I.F)=
  • 8.
    x2y6 y-5=x2 Putv=y-5 = -5y-6 + x2 =-5x2 Here P= , Q= I.F=e-5logx=x-5 The solution is v(I.F)= VX-5= dx +c VX-5= dx +c = x2 + c Y-5= x3 +cx5
  • 9.
     Case-2 Thegeneral solution is v(I.F)=