Evaluate
2-19i
Real Part
2
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3\left(-2\right)+3\left(-i\right)+8i\left(-2\right)+8\left(-1\right)i^{2}
Multiply complex numbers 3+8i and -2-i like you multiply binomials.
3\left(-2\right)+3\left(-i\right)+8i\left(-2\right)+8\left(-1\right)\left(-1\right)
By definition, i^{2} is -1.
-6-3i-16i+8
Do the multiplications.
-6+8+\left(-3-16\right)i
Combine the real and imaginary parts.
2-19i
Do the additions.
Re(3\left(-2\right)+3\left(-i\right)+8i\left(-2\right)+8\left(-1\right)i^{2})
Multiply complex numbers 3+8i and -2-i like you multiply binomials.
Re(3\left(-2\right)+3\left(-i\right)+8i\left(-2\right)+8\left(-1\right)\left(-1\right))
By definition, i^{2} is -1.
Re(-6-3i-16i+8)
Do the multiplications in 3\left(-2\right)+3\left(-i\right)+8i\left(-2\right)+8\left(-1\right)\left(-1\right).
Re(-6+8+\left(-3-16\right)i)
Combine the real and imaginary parts in -6-3i-16i+8.
Re(2-19i)
Do the additions in -6+8+\left(-3-16\right)i.
2
The real part of 2-19i is 2.
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