Question

please answer my question ​

Answer 1

Answer:

A

Explanation:

Let equivalent resistance be x then equivalent is also x

$x = r + r + \frac{rx}{r + x} \\ x(r + x) = 2r(r + x) + rx \\ {x}^{2} - 2rx - 2 {r}^{2} = 0 \\ x = \frac{2r \pm \: \sqrt{ {4r}^{2} + 8 {r}^{2} } }{2} = r( \sqrt{3} + 1)$