Question

a) 4^n+1-2^2n
b) 9 X 25^n-5^2n

Answer 1

A) ...    $4^{n+1}-2^{2n}=4^n*4-(2^2)^n}=4^n}*4-4^{n}=4^{n}(4-1)=3\cdot4^n$

B) ...    $9*25^n-5^{2n}=9*25^n-(5^2)^n=25^n(9-1)=8*25^n$