Question

What is the complex conjugate of `-2-sqrt5i`?

Answer 1

`-2+sqrt5i`.

Explanation:

The complex conjugate of `x+iy` is `x-iy`.

Hence, the complex conjugate of `-2-isqrt5` is

`-2+sqrt5i`.

Answer 2

`-2+sqrt5i`

Explanation:

Given a complex number `z=a+-bi`

Then the complex conjugate `barz` is

`color(red)(|bar(ul(color(white)(a/a)color(black)(barz=a∓bi)color(white)(a/a)|)))`

Note that the real part , remains unchanged while the `color(red)"sign"` of the imaginary part reverses.

Thus the conjugate is `-2+sqrt5i`