AP EAMCET · Maths · Complex Number
\(\sum_{k=1}^6\left[\sin \frac{2 k \pi}{7}-i \cos \frac{2 k \pi}{7}\right]\) is equal to
- A \(-1\)
- B \(0\)
- C \(-i\)
- D \(i\)
Answer & Solution
Correct Answer
(D) \(i\)
Step-by-step Solution
Detailed explanation
We have, \(\sum_{k=1}^6\left[\sin \frac{2 k \pi}{7}-i \cos \frac{2 \pi k}{7}\right]\)…
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