Evaluate
92+56i
Real Part
92
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-4-4\times \left(-12i\right)+8i\times 1+8\left(-12\right)i^{2}
Multiply complex numbers -4+8i and 1-12i like you multiply binomials.
-4-4\times \left(-12i\right)+8i\times 1+8\left(-12\right)\left(-1\right)
By definition, i^{2} is -1.
-4+48i+8i+96
Do the multiplications.
-4+96+\left(48+8\right)i
Combine the real and imaginary parts.
92+56i
Do the additions.
Re(-4-4\times \left(-12i\right)+8i\times 1+8\left(-12\right)i^{2})
Multiply complex numbers -4+8i and 1-12i like you multiply binomials.
Re(-4-4\times \left(-12i\right)+8i\times 1+8\left(-12\right)\left(-1\right))
By definition, i^{2} is -1.
Re(-4+48i+8i+96)
Do the multiplications in -4-4\times \left(-12i\right)+8i\times 1+8\left(-12\right)\left(-1\right).
Re(-4+96+\left(48+8\right)i)
Combine the real and imaginary parts in -4+48i+8i+96.
Re(92+56i)
Do the additions in -4+96+\left(48+8\right)i.
92
The real part of 92+56i is 92.
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