Question

(3-i).(7-i) me ajudem

Answer 1

(3 - i).(7 - i)
= 21 - 3i - 7i + i² 
= 21 - 10i + (- 1)
= 21 - 10i - 1
= 21 - 10i

(5 - 2i)(5 - 2i)
= 25 - 10i - 10i + (2i)²
= 25 - 20i + 4i²
= 25 - 20i + 4.(- 1)
= 25 - 20i - 4
= 21 - 20i