Q. If $y = 1 + x + x^{2} + x^{3} + ...$, then $x$ is equal to
A) $\frac{y - 1}{y}$
B) $\frac{1 - y}{y}$
C) $\frac{y}{a - y}$
D) None of these
Explanation
(a)
Since, $y = 1 + x + x^{2} + x^{3} + \ldots = \frac{1}{1 - x}$
$\therefore y - yx = 1\ \Rightarrow \ x = \frac{y - 1}{y}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.