Evaluate
6-8i
Real Part
6
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7\times 1+7\left(-i\right)-i-\left(-i^{2}\right)
Multiply complex numbers 7-i and 1-i like you multiply binomials.
7\times 1+7\left(-i\right)-i-\left(-\left(-1\right)\right)
By definition, i^{2} is -1.
7-7i-i-1
Do the multiplications.
7-1+\left(-7-1\right)i
Combine the real and imaginary parts.
6-8i
Do the additions.
Re(7\times 1+7\left(-i\right)-i-\left(-i^{2}\right))
Multiply complex numbers 7-i and 1-i like you multiply binomials.
Re(7\times 1+7\left(-i\right)-i-\left(-\left(-1\right)\right))
By definition, i^{2} is -1.
Re(7-7i-i-1)
Do the multiplications in 7\times 1+7\left(-i\right)-i-\left(-\left(-1\right)\right).
Re(7-1+\left(-7-1\right)i)
Combine the real and imaginary parts in 7-7i-i-1.
Re(6-8i)
Do the additions in 7-1+\left(-7-1\right)i.
6
The real part of 6-8i is 6.
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