Evaluate
-4i
Real Part
0
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2\times 1+2\left(-i\right)-2i-2\left(-1\right)i^{2}
Multiply complex numbers 2-2i and 1-i like you multiply binomials.
2\times 1+2\left(-i\right)-2i-2\left(-1\right)\left(-1\right)
By definition, i^{2} is -1.
2-2i-2i-2
Do the multiplications.
2-2+\left(-2-2\right)i
Combine the real and imaginary parts.
-4i
Do the additions.
Re(2\times 1+2\left(-i\right)-2i-2\left(-1\right)i^{2})
Multiply complex numbers 2-2i and 1-i like you multiply binomials.
Re(2\times 1+2\left(-i\right)-2i-2\left(-1\right)\left(-1\right))
By definition, i^{2} is -1.
Re(2-2i-2i-2)
Do the multiplications in 2\times 1+2\left(-i\right)-2i-2\left(-1\right)\left(-1\right).
Re(2-2+\left(-2-2\right)i)
Combine the real and imaginary parts in 2-2i-2i-2.
Re(-4i)
Do the additions in 2-2+\left(-2-2\right)i.
0
The real part of -4i is 0.
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
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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