Given:

We re – write the above equation

[∵, i² = -1]

Now, open the brackets,

= -2 × (-3) + (-2) × 2i√3 + i√3 × (-3) + i√3 × 2i√3

= 6 – 4i√3 – 3i√3 + 6i²

= 6 – 7i√3 + [6 × (-1)] [∵, i² = -1]

= 6 – 7i√3 – 6

= 0 – 7i√3