To simplify the expression 7 + 3i²i, we start by addressing the term i².
Recall that in complex numbers, i is defined as the imaginary unit, where i² = -1. Therefore, we can replace i² in the expression:
7 + 3(-1)i
This simplifies further to:
7 – 3i
So, the simplified form of the expression is 7 – 3i.