The capacitance of an infinite circuit formed by the repetition of the same link consisting of two identical capacitors, each with capacitance C (figure), is

Let capacitance between A and B be x. lf we remove the first two capacitors, then capacitance across D and E will also be x. So the circuit can be redrawn as follows: x=C(C+x)C+(C+x)Solve to get x=5−12C