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Complex Numbers
"Complex" numbers share many properties with the real numbers. In fact, complex numbers include all the real numbers, so you know lots of them already. Such an overachiever.
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Concept Quizzes
True or False:
For complex numbers \(a\) and \(b\),
\[ |a| + |b| = |a+b|. \]
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by Brilliant Staff
Evaluate
\[ i \times ( -i) . \]
Note: \(i \) is the imaginary unit, where \(i^2=-1\).
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For any complex number \(z\), which of the following must be equal to
"the real part of the imaginary part of \(z\)"?
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Which of the following is equal to
\[ \frac{ 1 + i } { 1 - i }? \]
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Are real numbers also complex numbers?
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by Brilliant Staff