(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The problem is from an NMAT Practice Exam. The problem is multiple choice.

3^(n+2)+(3^(n+3)-3^(n+1)) = ?

a.)1/(3^(n+1))

b.)1/(3^(n+2))

c.)3/8

d.)1/3

The answer given is 1/3, but I don't know how they got that.

2. Relevant equations

none

3. The attempt at a solution

My attempts:

3^(n+2)+(3^(n+3)-3^(n+1)) =3^(n)*(9+27-3)=33*3^n

Another attempt using self similarity...

y=3^(n+2)+(3^(n+3)-3^(n+1))

3y=3^(n+3)+(3^(n+4)-3^(n+2))

3y-y=3^(n+4)-2*3^(n+2)+3^(n+1)

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# Homework Help: NMAT Tricky Math Problem: 3^(n+2)+(3^(n+3)-3^(n+1)) = ?

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