Evaluate
-60+70i
Real Part
-60
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11\left(-1\right)+11\times \left(7i\right)+7i\left(-1\right)+7\times 7i^{2}
Multiply complex numbers 11+7i and -1+7i like you multiply binomials.
11\left(-1\right)+11\times \left(7i\right)+7i\left(-1\right)+7\times 7\left(-1\right)
By definition, i^{2} is -1.
-11+77i-7i-49
Do the multiplications.
-11-49+\left(77-7\right)i
Combine the real and imaginary parts.
-60+70i
Do the additions.
Re(11\left(-1\right)+11\times \left(7i\right)+7i\left(-1\right)+7\times 7i^{2})
Multiply complex numbers 11+7i and -1+7i like you multiply binomials.
Re(11\left(-1\right)+11\times \left(7i\right)+7i\left(-1\right)+7\times 7\left(-1\right))
By definition, i^{2} is -1.
Re(-11+77i-7i-49)
Do the multiplications in 11\left(-1\right)+11\times \left(7i\right)+7i\left(-1\right)+7\times 7\left(-1\right).
Re(-11-49+\left(77-7\right)i)
Combine the real and imaginary parts in -11+77i-7i-49.
Re(-60+70i)
Do the additions in -11-49+\left(77-7\right)i.
-60
The real part of -60+70i is -60.
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