A few days ago
checked.cherry

I need some help with a couple of indice/exponent questions?

Please tell me how to do these.

a)(2^(2n+3)-(2^n)^2)/2^n answer is 7(2^n)

b)(3^(n+1)+9)/3^(n-1)+1 answer is 9

Top 1 Answers
A few days ago
Anonymous

Favorite Answer

(a)

(2^(2n+3)-(2^n)^2)/2^n

Taking out a factor 2^(2n) from the numerator:

2^(2n) [ 2^3 – 1 ] / 2^n

= 2^n [ 8 – 1]

= 7(2^n).

(b)

If the answer is 9, then everything following the ‘/’ needs to be bracketed.

(3^(n+1)+9) / (3^(n-1)+1)

= 3^2 [3^(n – 1) + 1 ] / [3^(n – 1) + 1 ]

= 3^2

= 9.

0