Evaluate
-15+6i
Real Part
-15
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3i\times 2+3\times 5i^{2}
Multiply 3i times 2+5i.
3i\times 2+3\times 5\left(-1\right)
By definition, i^{2} is -1.
-15+6i
Do the multiplications. Reorder the terms.
Re(3i\times 2+3\times 5i^{2})
Multiply 3i times 2+5i.
Re(3i\times 2+3\times 5\left(-1\right))
By definition, i^{2} is -1.
Re(-15+6i)
Do the multiplications in 3i\times 2+3\times 5\left(-1\right). Reorder the terms.
-15
The real part of -15+6i is -15.
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