# Math Help - Maclaurin expansions

1. ## Maclaurin expansions

Use series multiplication to find a formula for in these Maclaurin expansions. In what circle is each series valid?

2. Originally Posted by lacy1104
Use series multiplication to find a formula for in these Maclaurin expansions. In what circle is each series valid?
The series for $\cosh(z)$ converges for all $z \in \mathbb{C}$ , and that for $\frac{1}{1-z}$ converges for $|z|<1$

RonL