Question

order of the differential equation of the family of all concentric circles centred at (h, k) is

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

The correct option is A 1

Equation of circle: $(x-h{)}^2+(y-k{)}^2=r^2$

Here, r is an arbitrary variable.

$\Rightarrow$ Order of differential equation $=1$ (number of variable).