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Complex conjugate

A complex conjugate pair is a pair of two complex numbers which are identical, except for that the sign of the imaginary part is different.

If w=x+yiw=x+yi, then the conjugate of ww is xyix-yi.

Representing the complex conjugate

The complex conjugate of a complex number, zz, is represented by zz^*.

Examples of complex conjugates

  • 5+2i5+2i and 52i5-2i
  • i+1-i+1 and 1+i1+i
  • 4i4i and 4i-4i

Complex roots

Complex roots come in conjugate pairs. This means that, if a complex number is a root of an equation, then the conjugate of that complex number is also a root.

Given that 5+4i5+4i is a root of an equation, find another root

  • 54i5-4i