Evaluate
65
Real Part
65
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8\times 8+8\left(-i\right)+8i-i^{2}
Multiply complex numbers 8+i and 8-i like you multiply binomials.
8\times 8+8\left(-i\right)+8i-\left(-1\right)
By definition, i^{2} is -1.
64-8i+8i+1
Do the multiplications.
64+1+\left(-8+8\right)i
Combine the real and imaginary parts.
65
Do the additions.
Re(8\times 8+8\left(-i\right)+8i-i^{2})
Multiply complex numbers 8+i and 8-i like you multiply binomials.
Re(8\times 8+8\left(-i\right)+8i-\left(-1\right))
By definition, i^{2} is -1.
Re(64-8i+8i+1)
Do the multiplications in 8\times 8+8\left(-i\right)+8i-\left(-1\right).
Re(64+1+\left(-8+8\right)i)
Combine the real and imaginary parts in 64-8i+8i+1.
Re(65)
Do the additions in 64+1+\left(-8+8\right)i.
65
The real part of 65 is 65.
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