Mathematics · 2022
JEE Main · 26 June 2022, Shift 2 · Q23
If z^2+z+1=0, z ∈ C, then |Σ_n=1^15(z^n+(-1)^n 1/z^n)^2| is equal to \ \ \ \.
If $\displaystyle z^2+z+1=0, z \in \mathbb{C}$, then $\displaystyle \left|\sum_{n=1}^{15}\left(z^n+(-1)^n \frac{1}{z^n}\right)^2\right|$ is equal to \_\_\_\_.
Official answer
2
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JEE Main 2022 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.