## anonymous 5 years ago 18 (sigma)(-1)^n2n n=4

1. anonymous

$\sum_{n=4}^{18}-1^{n^2n}$ ?? is this the question?

2. anonymous

yes

3. anonymous

actually its( -1^n) 2n

4. anonymous

oh well since it is negative one you know that it will either be 1 or negative 1 for each n in the middle of the paratheses, however since you have a 2n on the outside as an exponent that means that it will always be an even exponent so each time, the answer will be 1. so just go (18 - 4)(1) = 14

5. anonymous

my directions tell me to use a graphing calculator but i have no idea how to put sigma into a calculator?