Answer to Question #59453 in Differential Equations for Rita

Question

4 Find the total differential of the function u = x^2y−3y
I. 2x+(x^2−3)dy
II. 2xydx+x^2dy
III. 2xydx+(x^2−3)dy
IV. 2xydx+(x^3−2)dy
5 The total differential du of a function u (x, y) = 0 is defined as
I. ∂u/∂x dx+∂u.∂x dy=0
II. ∂u/∂x dy+∂u/∂x dy=0
III. ∂u/∂x dx+∂u/∂y dx=0
IV. ∂u/∂x dx+∂u/∂y dy=0
6 A differential equation involving only a single independent variable is called ………… equation.
I. extraordinary differential
II. ordinary differential
III. super-ordinary differential
IV. partial differential
7 The homogeneous equation d/ydx=x^4+x^3y+y^4/3x^3y+y^4 is of …… degree
I. first , II. second , III. third , IV. fourth