Evaluate
72+24i
Real Part
72
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8i\times 3+8\left(-9\right)i^{2}
Multiply 8i times 3-9i.
8i\times 3+8\left(-9\right)\left(-1\right)
By definition, i^{2} is -1.
72+24i
Do the multiplications. Reorder the terms.
Re(8i\times 3+8\left(-9\right)i^{2})
Multiply 8i times 3-9i.
Re(8i\times 3+8\left(-9\right)\left(-1\right))
By definition, i^{2} is -1.
Re(72+24i)
Do the multiplications in 8i\times 3+8\left(-9\right)\left(-1\right). Reorder the terms.
72
The real part of 72+24i is 72.
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