Practice question · Sort into groups
Sort each number by whether it is real, purely imaginary, or a general complex number.
Groups: Real · Purely imaginary · General complex
- 2 + 3i
- -1
- -4i
- 5i
- 7
Hints
- Real numbers have zero imaginary part; purely imaginary have zero real part.
- A general complex number has both parts nonzero.
Show the answer
Real: 7, -1
Purely imaginary: 5i, -4i
General complex: 2 + 3i
Why
7 and -1 have no imaginary part (real). 5i and -4i have no real part (purely imaginary). 2 + 3i has both parts nonzero (general complex).
Practise Complex Numbers
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