Jee Main
Complex Numbers
JEE Main 2022 (Online) 26th June Evening Shift
INTEGER+4 / -12022
If \({z^2} + z + 1 = 0\), \(z \in C\), then
\(\left| {\sum\limits_{n = 1}^{15} {{{\left( {{z^n} + {{( - 1)}^n}{1 \over {{z^n}}}} \right)}^2}} } \right|\) is equal to _________.