Evaluate
20
Real Part
20
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-2\left(-2\right)-2\times \left(-4i\right)+4i\left(-2\right)+4\left(-4\right)i^{2}
Multiply complex numbers -2+4i and -2-4i like you multiply binomials.
-2\left(-2\right)-2\times \left(-4i\right)+4i\left(-2\right)+4\left(-4\right)\left(-1\right)
By definition, i^{2} is -1.
4+8i-8i+16
Do the multiplications.
4+16+\left(8-8\right)i
Combine the real and imaginary parts.
20
Do the additions.
Re(-2\left(-2\right)-2\times \left(-4i\right)+4i\left(-2\right)+4\left(-4\right)i^{2})
Multiply complex numbers -2+4i and -2-4i like you multiply binomials.
Re(-2\left(-2\right)-2\times \left(-4i\right)+4i\left(-2\right)+4\left(-4\right)\left(-1\right))
By definition, i^{2} is -1.
Re(4+8i-8i+16)
Do the multiplications in -2\left(-2\right)-2\times \left(-4i\right)+4i\left(-2\right)+4\left(-4\right)\left(-1\right).
Re(4+16+\left(8-8\right)i)
Combine the real and imaginary parts in 4+8i-8i+16.
Re(20)
Do the additions in 4+16+\left(8-8\right)i.
20
The real part of 20 is 20.
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