Evaluate
-9+2i
Real Part
-9
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3i\times 2+3\times 5i^{2}+2\left(3-2i\right)
Multiply 3i times 2+5i.
3i\times 2+3\times 5\left(-1\right)+2\left(3-2i\right)
By definition, i^{2} is -1.
-15+6i+2\left(3-2i\right)
Do the multiplications in 3i\times 2+3\times 5\left(-1\right). Reorder the terms.
-15+6i+2\times 3+2\times \left(-2i\right)
Multiply 2 times 3-2i.
-15+6i+\left(6-4i\right)
Do the multiplications in 2\times 3+2\times \left(-2i\right).
-15+6+\left(6-4\right)i
Combine the real and imaginary parts.
-9+2i
Do the additions.
Re(3i\times 2+3\times 5i^{2}+2\left(3-2i\right))
Multiply 3i times 2+5i.
Re(3i\times 2+3\times 5\left(-1\right)+2\left(3-2i\right))
By definition, i^{2} is -1.
Re(-15+6i+2\left(3-2i\right))
Do the multiplications in 3i\times 2+3\times 5\left(-1\right). Reorder the terms.
Re(-15+6i+2\times 3+2\times \left(-2i\right))
Multiply 2 times 3-2i.
Re(-15+6i+\left(6-4i\right))
Do the multiplications in 2\times 3+2\times \left(-2i\right).
Re(-15+6+\left(6-4\right)i)
Combine the real and imaginary parts in -15+6i+6-4i.
Re(-9+2i)
Do the additions in -15+6+\left(6-4\right)i.
-9
The real part of -9+2i is -9.
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Limits
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