Problem #PRU-5088

Problem

Let’s compute the infinite sum: $1 + 2 + 4 + 8 + 16 + . . . + 2^{n} + . . . = c$ Observe that $1 + 2 + 4 + 8 + . . . = 1 + 2 (1 + 2 + 4 + 8 + 16 + . . .)$ , namely $c = 1 + 2 c$ , then it follows that $c = 1 + 2 + 4 + 8 + . . . = - 1.$

To see the solution register and get verified.