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If the conjugate of a complex number is given by 1/(i−1), then the complex number is:

1. −1/(i−1)
2. 1/(i+1)
3. −1/(i+1)
4. 1/(i−1)

Correct answer: −1/(i+1)

Solution

The conjugate of a complex number is obtained by changing the sign of its imaginary part. Since the given conjugate is 1/(i−1), the original complex number must be the negative of the conjugate of that expression, which simplifies to −1/(i+1).

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