Question

The order of differential equation of family of all concentric circles centered at $(h,k)$ is

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

The correct option is A 1

Equation of circle : $(x-h{)}^2+(y-k{)}^2=r^2$ where 'r' is radius of the circle

Here (h, k) are given constants and only radius 'r' is the variable

Hence given equation contains only 1 variable

Therefore order of DE =1