Evaluate
-2-6i
Real Part
-2
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1\times 2+1\times \left(-4i\right)-i\times 2-\left(-4i^{2}\right)
Multiply complex numbers 1-i and 2-4i like you multiply binomials.
1\times 2+1\times \left(-4i\right)-i\times 2-\left(-4\left(-1\right)\right)
By definition, i^{2} is -1.
2-4i-2i-4
Do the multiplications.
2-4+\left(-4-2\right)i
Combine the real and imaginary parts.
-2-6i
Do the additions.
Re(1\times 2+1\times \left(-4i\right)-i\times 2-\left(-4i^{2}\right))
Multiply complex numbers 1-i and 2-4i like you multiply binomials.
Re(1\times 2+1\times \left(-4i\right)-i\times 2-\left(-4\left(-1\right)\right))
By definition, i^{2} is -1.
Re(2-4i-2i-4)
Do the multiplications in 1\times 2+1\times \left(-4i\right)-i\times 2-\left(-4\left(-1\right)\right).
Re(2-4+\left(-4-2\right)i)
Combine the real and imaginary parts in 2-4i-2i-4.
Re(-2-6i)
Do the additions in 2-4+\left(-4-2\right)i.
-2
The real part of -2-6i is -2.
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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