Evaluate
-2-8i
Real Part
-2
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-2i\times 4-2\left(-1\right)i^{2}
Multiply -2i times 4-i.
-2i\times 4-2\left(-1\right)\left(-1\right)
By definition, i^{2} is -1.
-2-8i
Do the multiplications. Reorder the terms.
Re(-2i\times 4-2\left(-1\right)i^{2})
Multiply -2i times 4-i.
Re(-2i\times 4-2\left(-1\right)\left(-1\right))
By definition, i^{2} is -1.
Re(-2-8i)
Do the multiplications in -2i\times 4-2\left(-1\right)\left(-1\right). Reorder the terms.
-2
The real part of -2-8i is -2.
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