Verified answer

i=√-1

i² = -1

a

(2-i)(2+i) - (3-2i) + 7 = 2² - i² - 3 + 2i + 7 = 4 + 1 - 3 + 2i + 7 = 9 + 2i

б

(1 + i)⁴ = (1 + i)²(1 + i)² = (1+ 2i + i²)(1 + 2i + i²) = (1 + 2i - 1)(1+ 2i - 1) = 2i*2i = 4i² = -4

а)

b)