Evaluate
42+63i
Real Part
42
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7i\times 9+7\left(-6\right)i^{2}
Multiply 7i times 9-6i.
7i\times 9+7\left(-6\right)\left(-1\right)
By definition, i^{2} is -1.
42+63i
Do the multiplications. Reorder the terms.
Re(7i\times 9+7\left(-6\right)i^{2})
Multiply 7i times 9-6i.
Re(7i\times 9+7\left(-6\right)\left(-1\right))
By definition, i^{2} is -1.
Re(42+63i)
Do the multiplications in 7i\times 9+7\left(-6\right)\left(-1\right). Reorder the terms.
42
The real part of 42+63i is 42.
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