Mathematics cbse 12th

 QUESTION 1:

    Which of the the following differential equations cannot be solved, using variable                     separable   method

       ANS :(y^2-2xy) dx = (x^2-2xy)dy

 QUESTION 2:

    The integrating factor of the differential equation x Dy/dx -y =2 x^2 is :

       ANS :1/x

 QUESTION 3:

       The solution of the differential equation: 2x Dy/dx -y =3 represents a family of:

        ANS :Parabolas

 QUESTION 4:

       The integrating factor of the differential equation x dy/dx- 3y = e^- 2 x is,

         ANS : 1/x^3

 QUESTION 5:

        The number of arbitrary constants in the the general solution of a differential equation of          order 4 is is

           ANS : 4

QUESTION 6:

          I F of the differential equation DY /DX + 2y =e^ 2x is

            ANS :e^2x

 QUESTION 7:

         The degree of of differential equation y''^3 +y'^2+sin (y')+1= 0 is

             ANS: 3

 QUESTION 8:

         An integrating factor of the differential equation ; sin x dy/dx + 2y cos x= 1 is,

           ANS : sin^2x

 QUESTION 9:

       The general solution of the differential equation dy/dx+y/x=3x is

         ANS: Y =X^2-C/X

 

 QUESTION 10:

      Solution of the differential equation :cos x dy= y(sinx-y) dx is

       ANS: sec x = ( tanx +c)y