Evaluate
-8-56i
Real Part
-8
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8\times 2+8\times \left(-6i\right)-4i\times 2-4\left(-6\right)i^{2}
Multiply complex numbers 8-4i and 2-6i like you multiply binomials.
8\times 2+8\times \left(-6i\right)-4i\times 2-4\left(-6\right)\left(-1\right)
By definition, i^{2} is -1.
16-48i-8i-24
Do the multiplications.
16-24+\left(-48-8\right)i
Combine the real and imaginary parts.
-8-56i
Do the additions.
Re(8\times 2+8\times \left(-6i\right)-4i\times 2-4\left(-6\right)i^{2})
Multiply complex numbers 8-4i and 2-6i like you multiply binomials.
Re(8\times 2+8\times \left(-6i\right)-4i\times 2-4\left(-6\right)\left(-1\right))
By definition, i^{2} is -1.
Re(16-48i-8i-24)
Do the multiplications in 8\times 2+8\times \left(-6i\right)-4i\times 2-4\left(-6\right)\left(-1\right).
Re(16-24+\left(-48-8\right)i)
Combine the real and imaginary parts in 16-48i-8i-24.
Re(-8-56i)
Do the additions in 16-24+\left(-48-8\right)i.
-8
The real part of -8-56i is -8.
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