Evaluate
-12-9i
Real Part
-12
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3i\left(-3\right)+3\times 4i^{2}
Multiply 3i times -3+4i.
3i\left(-3\right)+3\times 4\left(-1\right)
By definition, i^{2} is -1.
-12-9i
Do the multiplications. Reorder the terms.
Re(3i\left(-3\right)+3\times 4i^{2})
Multiply 3i times -3+4i.
Re(3i\left(-3\right)+3\times 4\left(-1\right))
By definition, i^{2} is -1.
Re(-12-9i)
Do the multiplications in 3i\left(-3\right)+3\times 4\left(-1\right). Reorder the terms.
-12
The real part of -12-9i is -12.
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