Question

(4^(n+1)-4^n)/(15+4^n)

Answer 1

см. рисунок...................................................................

Answer 2

(4^(n+1)-4^n)/(15*4^n)=4^(n+1)/15/4^n-4^n/15/4^n=4/15-4^n/15/4^n=4/15-1^n/15=4/15-1/15=4/15-1/15=0.2