Solve for z
z=\frac{4}{5}+\frac{2}{5}i=0.8+0.4i
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\left(3+i\right)z-\left(2i-i^{2}\right)=1
Multiply i times 2-i.
\left(3+i\right)z-\left(2i-\left(-1\right)\right)=1
By definition, i^{2} is -1.
\left(3+i\right)z-\left(1+2i\right)=1
Do the multiplications in 2i-\left(-1\right). Reorder the terms.
\left(3+i\right)z=1+\left(1+2i\right)
Add 1+2i to both sides.
\left(3+i\right)z=1+1+2i
Combine the real and imaginary parts in numbers 1 and 1+2i.
\left(3+i\right)z=2+2i
Add 1 to 1.
z=\frac{2+2i}{3+i}
Divide both sides by 3+i.
z=\frac{\left(2+2i\right)\left(3-i\right)}{\left(3+i\right)\left(3-i\right)}
Multiply both numerator and denominator of \frac{2+2i}{3+i} by the complex conjugate of the denominator, 3-i.
z=\frac{\left(2+2i\right)\left(3-i\right)}{3^{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(2+2i\right)\left(3-i\right)}{10}
By definition, i^{2} is -1. Calculate the denominator.
z=\frac{2\times 3+2\left(-i\right)+2i\times 3+2\left(-1\right)i^{2}}{10}
Multiply complex numbers 2+2i and 3-i like you multiply binomials.
z=\frac{2\times 3+2\left(-i\right)+2i\times 3+2\left(-1\right)\left(-1\right)}{10}
By definition, i^{2} is -1.
z=\frac{6-2i+6i+2}{10}
Do the multiplications in 2\times 3+2\left(-i\right)+2i\times 3+2\left(-1\right)\left(-1\right).
z=\frac{6+2+\left(-2+6\right)i}{10}
Combine the real and imaginary parts in 6-2i+6i+2.
z=\frac{8+4i}{10}
Do the additions in 6+2+\left(-2+6\right)i.
z=\frac{4}{5}+\frac{2}{5}i
Divide 8+4i by 10 to get \frac{4}{5}+\frac{2}{5}i.
Examples
Quadratic equation
{ 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}