You can put this solution on YOUR website! we are given,
2+4x+8x^2+16x^3+32x^4+..... which can be written
a / (1 - r) where a is first term and r is common ratio, r = 2x and
division by 0 is not allowed, then
summation(S) for k = 0 to infinity of (2^(k+1)*x^k) is
S = 2 / (1 - 2x) where |x| < (1/2)
