thx

HP5049 :

thx

(a)
3^n+1 * 9^-2n-3
=3^n+1 * 3^2(-2n-3)
=3^n+(-4n)+1+(-6)
=3^-3n-5
(b)
5^2n+1 / 25^n-1
=5^2n+1 / 5^2(n-1)
=5^2n-2n+1-2
=5^-1
=1/5
(c)
8^3n+1 / 16^2n
=2^3(3n+1) / 2^4(2n)
=2^9n-8n+3
=2^n+3

記得將兩個項個常數整到一樣先好計