Evaluate
58
Real Part
58
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-3\left(-3\right)-3\times \left(7i\right)-7i\left(-3\right)-7\times 7i^{2}
Multiply complex numbers -3-7i and -3+7i like you multiply binomials.
-3\left(-3\right)-3\times \left(7i\right)-7i\left(-3\right)-7\times 7\left(-1\right)
By definition, i^{2} is -1.
9-21i+21i+49
Do the multiplications.
9+49+\left(-21+21\right)i
Combine the real and imaginary parts.
58
Do the additions.
Re(-3\left(-3\right)-3\times \left(7i\right)-7i\left(-3\right)-7\times 7i^{2})
Multiply complex numbers -3-7i and -3+7i like you multiply binomials.
Re(-3\left(-3\right)-3\times \left(7i\right)-7i\left(-3\right)-7\times 7\left(-1\right))
By definition, i^{2} is -1.
Re(9-21i+21i+49)
Do the multiplications in -3\left(-3\right)-3\times \left(7i\right)-7i\left(-3\right)-7\times 7\left(-1\right).
Re(9+49+\left(-21+21\right)i)
Combine the real and imaginary parts in 9-21i+21i+49.
Re(58)
Do the additions in 9+49+\left(-21+21\right)i.
58
The real part of 58 is 58.
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