Question

Simplification (2+i)(2-i) is​

Answer 1

Step-by-step explanation:

(2+i)(2-i)

= 4 +2i-2i-i^2

= 4-i^2

= 4-(-1) [ i^2=-1]

=4+1

=5

Answer 2

(a +b)(a-b) = a² - b²

(2+i)(2-i) = 2² - i²

= 4 - i²