== Complex Number == Complex Number is a number that can be expressed mathematically as a sum of a Real Number and an Imaginary Number Z = A + j B {\displaystyle Z=A+jB} Z = | Z | ∠ θ {\displaystyle Z=|Z|\angle \theta } | Z | = A 2 + B 2 {\displaystyle |Z|={\sqrt {A^{2}+B^{2}}}} θ = T a n − 1 B A {\displaystyle \theta =Tan^{-}1{\frac {B}{A}}} == Complex Conjugate Number == Z = A − j B {\displaystyle Z=A-jB} Z = | Z | ∠ − θ {\displaystyle Z=|Z|\angle -\theta } | Z | = A 2 + B 2 {\displaystyle |Z|={\sqrt {A^{2}+B^{2}}}} θ = − T a n − 1 B A {\displaystyle \theta =-Tan^{-}1{\frac {B}{A}}} == Rules == If there are two Complex Numbers Z 1 = A + j B {\displaystyle Z_{1}=A+jB} Z 2 = C + j D {\displaystyle Z_{2}=C+jD} (A + jB) + (C + jD) = (A + C) + j (B + D) (A + jB) - (C + jD) = (A - C) + j (B - D) (A + jB) x (C + jD) = (AC + BD) + j (AD + BC) ( A + j B ) ( C + j D ) {\displaystyle {\frac {(A+jB)}{(C+jD)}}} = ( A + j B ) ( C − j D ) ( C + j D ) ( C − j D ) {\displaystyle {\frac {(A+jB)(C-jD)}{(C+jD)(C-jD)}}} = ( A C + B D ) + j ( B C − A D ) C 2 + D 2 {\displaystyle {\frac {(AC+BD)+j(BC-AD)}{C^{2}+D^{2}}}} Z 1 × Z 2 = | Z 1 | | Z 2 | ∠ ( θ 1 + θ 2 ) {\displaystyle Z_{1}\times Z_{2}=|Z_{1}||Z_{2}|\angle (\theta _{1}+\theta _{2})} Z 1 / Z 2 = | Z 1 | | Z 2 | ∠ ( θ 1 − θ 2 ) {\displaystyle Z_{1}/Z_{2}={\frac {|Z_{1}|}{|Z_{2}|}}\angle (\theta _{1}-\theta _{2})}