Evaluate
3-28i
Real Part
3
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5\times 3+5\times \left(-2i\right)-6i\times 3-6\left(-2\right)i^{2}
Multiply complex numbers 5-6i and 3-2i like you multiply binomials.
5\times 3+5\times \left(-2i\right)-6i\times 3-6\left(-2\right)\left(-1\right)
By definition, i^{2} is -1.
15-10i-18i-12
Do the multiplications.
15-12+\left(-10-18\right)i
Combine the real and imaginary parts.
3-28i
Do the additions.
Re(5\times 3+5\times \left(-2i\right)-6i\times 3-6\left(-2\right)i^{2})
Multiply complex numbers 5-6i and 3-2i like you multiply binomials.
Re(5\times 3+5\times \left(-2i\right)-6i\times 3-6\left(-2\right)\left(-1\right))
By definition, i^{2} is -1.
Re(15-10i-18i-12)
Do the multiplications in 5\times 3+5\times \left(-2i\right)-6i\times 3-6\left(-2\right)\left(-1\right).
Re(15-12+\left(-10-18\right)i)
Combine the real and imaginary parts in 15-10i-18i-12.
Re(3-28i)
Do the additions in 15-12+\left(-10-18\right)i.
3
The real part of 3-28i is 3.
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Matrix
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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
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Limits
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