Solve for z
z=-1+7i
Assign z
z≔-1+7i
Share
Copied to clipboard
z=\frac{5i\left(2+i\right)}{\left(2-i\right)\left(2+i\right)}+5i
Multiply both numerator and denominator of \frac{5i}{2-i} by the complex conjugate of the denominator, 2+i.
z=\frac{5i\left(2+i\right)}{2^{2}-i^{2}}+5i
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{5i\left(2+i\right)}{5}+5i
By definition, i^{2} is -1. Calculate the denominator.
z=\frac{5i\times 2+5i^{2}}{5}+5i
Multiply 5i times 2+i.
z=\frac{5i\times 2+5\left(-1\right)}{5}+5i
By definition, i^{2} is -1.
z=\frac{-5+10i}{5}+5i
Do the multiplications in 5i\times 2+5\left(-1\right). Reorder the terms.
z=-1+2i+5i
Divide -5+10i by 5 to get -1+2i.
z=-1+\left(2+5\right)i
Combine the real and imaginary parts in numbers -1+2i and 5i.
z=-1+7i
Add 2 to 5.
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}