Evaluate
17-i
Real Part
17
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7\times 2+7\left(-i\right)+3i\times 2+3\left(-1\right)i^{2}
Multiply complex numbers 7+3i and 2-i like you multiply binomials.
7\times 2+7\left(-i\right)+3i\times 2+3\left(-1\right)\left(-1\right)
By definition, i^{2} is -1.
14-7i+6i+3
Do the multiplications.
14+3+\left(-7+6\right)i
Combine the real and imaginary parts.
17-i
Do the additions.
Re(7\times 2+7\left(-i\right)+3i\times 2+3\left(-1\right)i^{2})
Multiply complex numbers 7+3i and 2-i like you multiply binomials.
Re(7\times 2+7\left(-i\right)+3i\times 2+3\left(-1\right)\left(-1\right))
By definition, i^{2} is -1.
Re(14-7i+6i+3)
Do the multiplications in 7\times 2+7\left(-i\right)+3i\times 2+3\left(-1\right)\left(-1\right).
Re(14+3+\left(-7+6\right)i)
Combine the real and imaginary parts in 14-7i+6i+3.
Re(17-i)
Do the additions in 14+3+\left(-7+6\right)i.
17
The real part of 17-i is 17.
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