Evaluate
2-4i
Real Part
2
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1\times 3+1\left(-i\right)-i\times 3-\left(-i^{2}\right)
Multiply complex numbers 1-i and 3-i like you multiply binomials.
1\times 3+1\left(-i\right)-i\times 3-\left(-\left(-1\right)\right)
By definition, i^{2} is -1.
3-i-3i-1
Do the multiplications.
3-1+\left(-1-3\right)i
Combine the real and imaginary parts.
2-4i
Do the additions.
Re(1\times 3+1\left(-i\right)-i\times 3-\left(-i^{2}\right))
Multiply complex numbers 1-i and 3-i like you multiply binomials.
Re(1\times 3+1\left(-i\right)-i\times 3-\left(-\left(-1\right)\right))
By definition, i^{2} is -1.
Re(3-i-3i-1)
Do the multiplications in 1\times 3+1\left(-i\right)-i\times 3-\left(-\left(-1\right)\right).
Re(3-1+\left(-1-3\right)i)
Combine the real and imaginary parts in 3-i-3i-1.
Re(2-4i)
Do the additions in 3-1+\left(-1-3\right)i.
2
The real part of 2-4i is 2.
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
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