Solve for z
z=-2i
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2-\left(2\times 1+2i\right)z=4i-2
Multiply 2 times 1+i.
2-\left(2+2i\right)z=4i-2
Do the multiplications in 2\times 1+2i.
2+\left(-2-2i\right)z=4i-2
Multiply -1 and 2+2i to get -2-2i.
\left(-2-2i\right)z=4i-2-2
Subtract 2 from both sides.
\left(-2-2i\right)z=-2-2+4i
Combine the real and imaginary parts in 4i-2-2.
\left(-2-2i\right)z=-4+4i
Add -2 to -2.
z=\frac{-4+4i}{-2-2i}
Divide both sides by -2-2i.
z=\frac{\left(-4+4i\right)\left(-2+2i\right)}{\left(-2-2i\right)\left(-2+2i\right)}
Multiply both numerator and denominator of \frac{-4+4i}{-2-2i} by the complex conjugate of the denominator, -2+2i.
z=\frac{\left(-4+4i\right)\left(-2+2i\right)}{\left(-2\right)^{2}-2^{2}i^{2}}
Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}.
z=\frac{\left(-4+4i\right)\left(-2+2i\right)}{8}
By definition, i^{2} is -1. Calculate the denominator.
z=\frac{-4\left(-2\right)-4\times \left(2i\right)+4i\left(-2\right)+4\times 2i^{2}}{8}
Multiply complex numbers -4+4i and -2+2i like you multiply binomials.
z=\frac{-4\left(-2\right)-4\times \left(2i\right)+4i\left(-2\right)+4\times 2\left(-1\right)}{8}
By definition, i^{2} is -1.
z=\frac{8-8i-8i-8}{8}
Do the multiplications in -4\left(-2\right)-4\times \left(2i\right)+4i\left(-2\right)+4\times 2\left(-1\right).
z=\frac{8-8+\left(-8-8\right)i}{8}
Combine the real and imaginary parts in 8-8i-8i-8.
z=\frac{-16i}{8}
Do the additions in 8-8+\left(-8-8\right)i.
z=-2i
Divide -16i by 8 to get -2i.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
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
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}