# Solving for a Variable in a Series

• May 5th 2009, 05:43 PM
ZosoPage
Solving for a Variable in a Series
• May 5th 2009, 06:01 PM
mr fantastic
Quote:

Originally Posted by ZosoPage

• May 6th 2009, 10:18 AM
ZosoPage
Sorry. Here is the problem again.

Solve exactly for the variable, x.

$x-(1/2)x^2+(1/3)x^3+...=0.2$
• May 6th 2009, 10:24 AM
skeeter
Quote:

Originally Posted by ZosoPage
Sorry. Here is the problem again.

Solve exactly for the variable, x.

$x-(1/2)x^2+(1/3)x^3+...=0.2$

note that ...

$\ln(1+x) = x - \frac{x^2}{2} + \frac{x^3}{3} - \frac{x^4}{4} + ...$