Introducing complex numbers to engineers can be effectively achieved by using tangible examples that relate to their field. Roots of unity and the representation of sine and cosine functions as rotating vectors on the complex plane provide accessible geometric interpretations. These concepts are particularly relevant in AC circuit analysis, where phasor diagrams illustrate the role of complex numbers in understanding impedance from inductors and capacitors. Additionally, complex numbers are essential in studying the responses of LRC circuits and transfer functions, which are commonly encountered in engineering curricula. Engaging students with practical applications can enhance their understanding and appreciation of complex numbers.