Evaluate
21+8i
Real Part
21
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19+2+\left(-1+9\right)i
Combine the real and imaginary parts in numbers 19-i and 2+9i.
21+8i
Add 19 to 2. Add -1 to 9.
Re(19+2+\left(-1+9\right)i)
Combine the real and imaginary parts in numbers 19-i and 2+9i.
Re(21+8i)
Add 19 to 2. Add -1 to 9.
21
The real part of 21+8i is 21.
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