Infinite GP
Algebra
Level
2
\[\large \begin{cases} x=1+a+a^2+a^3+\cdots \\ y=1+b+b^2+b^3+\cdots \end{cases} \]
For \( |a|, |b| < 1 \), define \(x\) and \(y\) as above. Find the value of
\[1+ab+a^2b^2+a^3b^3+\cdots. \]
by
Ojas Singh Malhi