How to solve for x ? Calculus Tests of Convergence / Divergence Infinite Series 1 Answer A. S. Adikesavan May 14, 2016 #x = 23/25# Explanation: Use #1/(1-x)=sumx^(n-1), n=1, 2, ..oo, |x|<1# Here, #2/(1-x)=25# So, #x = 23/25# < 1.. Answer link Related questions How can an infinite series have a finite sum? How do you evaluate an infinite series? How do you find the sum of an infinite series? How does an infinite geometric series apply to being pushed on a swing? What are infinite series used for? What is a convergent infinite series? What is a divergent infinite series? What is a partial sum of an infinite series? What is an oscillating infinite series? What is a telescoping infinite series? See all questions in Infinite Series Impact of this question 1744 views around the world You can reuse this answer Creative Commons License