by Guest » Thu May 21, 2020 11:38 am
[tex]a^n \times a^m = a^{n+m}[/tex]
[tex]a^n + a^m =[/tex] there are no such a formula
But if we have [tex]m > n[/tex] we can write
[tex]a^n + a^m = a^n(1 + a^{m-n})[/tex]
In your case you have
[tex]a + a =2a[/tex] where [tex]a = 2^2[/tex]
So
[tex]2^2+2^2 = 2\cdot 2^2=2\cdot 4[/tex]