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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
What is the absolute value of the complex number \[12+5i?\]
Details and assumptions
\(i\) is the imaginary number that satisfies \(i^2 = -1\).
Excel in math and science
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by Brilliant Staff
Is it true that \(\text{Re}(\text{Im}(z)) = \text{Im}(\text{Re}(z))\) for all complex numbers \(z\)?
Excel in math and science
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What is the value of \[ \left(9 + \sqrt{-81}\right)\left(20 - \sqrt{-400}\right)? \]
Excel in math and science
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Simplify \(\frac{4+2i}{2-i}\).
Details and assumptions
\(i\) is the imaginary number that satisfies \(i^2 = -1\).
Excel in math and science
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Which set of complex numbers satisfy the equation \(iz + \overline{z} = 0\)?
Hint: Start by letting \(z = x + iy\).
Excel in math and science
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by Brilliant Staff