Explanation:
when the exponent is an even number, the value is -1 and real.
when the exponent is uneven (odd), then the result is i and therefore imaginary.
i¹⁴ real
i⁴³ imaginary
i⁷ imaginary
i¹⁰ real
(4 - 5i)² = 4² - 40i + 25i² = 16 - 40i - 25 = -9 -40i imaginary
(7 + 2i)(7 - 2i) = 49 - 4i² = 49 + 4 = 53 real