Evaluate
25-5i
Real Part
25
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-5\left(-2\right)-5\times \left(3i\right)-5i\left(-2\right)-5\times 3i^{2}
Multiply complex numbers -5-5i and -2+3i like you multiply binomials.
-5\left(-2\right)-5\times \left(3i\right)-5i\left(-2\right)-5\times 3\left(-1\right)
By definition, i^{2} is -1.
10-15i+10i+15
Do the multiplications.
10+15+\left(-15+10\right)i
Combine the real and imaginary parts.
25-5i
Do the additions.
Re(-5\left(-2\right)-5\times \left(3i\right)-5i\left(-2\right)-5\times 3i^{2})
Multiply complex numbers -5-5i and -2+3i like you multiply binomials.
Re(-5\left(-2\right)-5\times \left(3i\right)-5i\left(-2\right)-5\times 3\left(-1\right))
By definition, i^{2} is -1.
Re(10-15i+10i+15)
Do the multiplications in -5\left(-2\right)-5\times \left(3i\right)-5i\left(-2\right)-5\times 3\left(-1\right).
Re(10+15+\left(-15+10\right)i)
Combine the real and imaginary parts in 10-15i+10i+15.
Re(25-5i)
Do the additions in 10+15+\left(-15+10\right)i.
25
The real part of 25-5i is 25.
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Limits
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