Thread: Find power series representation and interval of convergence.

The problem:



My attempt:



With |-9x^2| < 1, 9x < 1, x < 1/9
R = 1/9, I = (-1/9, 1/9)

Not sure if this is correct. Thanks

That's a good way to start: you recognized that is the sum of the geometric series and here r= -9x^2[/tex]. However, does NOT give 9x< 1, it gives so that

You're right, rookie mistake