a + bi where a is real and b is imaginary.r∠θ with r = √(a²+b²), θ = atan2(b, a) (radians).(a±c) + (b±d)i.(a+bi)(c+di) = (ac−bd) + (ad+bc)i.(a+bi)/(c+di) = [(ac+bd) + (bc−ad)i]/(c²+d²).conj(a+bi) = a − bi.(r∠θ)^n = r^n ∠ nθ for integer n.θ ∈ (−π, π] (via atan2).i or j; allow 3+4i, 5, -7i.(2+3i) + (4−5i) = 6 − 2i(3+4i)(1−2i) = 11 − 2i(1+2i)/(3−4i) = (−0.2) + 0.4i(1+i)^5 = −4 + 4i−3+4i ⇒ r=5, θ≈2.2143 rad (126.87°)Choose which optional categories you allow. Necessary cookies are always on. Privacy Policy.