Evaluate
145
Real Part
145
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12\times 12+12i-i\times 12-i^{2}
Multiply complex numbers 12-i and 12+i like you multiply binomials.
12\times 12+12i-i\times 12-\left(-1\right)
By definition, i^{2} is -1.
144+12i-12i+1
Do the multiplications.
144+1+\left(12-12\right)i
Combine the real and imaginary parts.
145
Do the additions.
Re(12\times 12+12i-i\times 12-i^{2})
Multiply complex numbers 12-i and 12+i like you multiply binomials.
Re(12\times 12+12i-i\times 12-\left(-1\right))
By definition, i^{2} is -1.
Re(144+12i-12i+1)
Do the multiplications in 12\times 12+12i-i\times 12-\left(-1\right).
Re(144+1+\left(12-12\right)i)
Combine the real and imaginary parts in 144+12i-12i+1.
Re(145)
Do the additions in 144+1+\left(12-12\right)i.
145
The real part of 145 is 145.
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