Question

1 The order of a differential equation is the
I. order of the highest order derivative appearing in the equation
II. order of the lowest order derivative appearing in the equation
III. order of the second highest order derivative appearing in the equation
Iv. last order of the highest order derivative appearing in the equation
2 If u = f(x,y) be a function of two independent variables x and y, then ∂u/∂y is equal to

i. lim△x→0f(x+△x,y)−f(x,y)/△x

II. lim△y→0f(x,y+△y)−f(x,y)/△y

iii.limy→0f(x,y+△y)−f(x,y)/△y

IV.lim△y→0f(x+△x,y)−f(x,y)/△x
3 The general solution of a first order differential equation normally contains one arbitrary constant which is called a …………..
I. family of curves

ii. perimeter

III. curve

IV. parameter