Evaluate
-18+i
Real Part
-18
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i-21+3
The opposite of -3 is 3.
-21+3+i
Combine the real and imaginary parts.
-18+i
Add -21 to 3.
Re(i-21+3)
The opposite of -3 is 3.
Re(-21+3+i)
Combine the real and imaginary parts in i-21+3.
Re(-18+i)
Add -21 to 3.
-18
The real part of -18+i is -18.
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