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Simplify \(\frac{3(2^{n+1}) - 4(2^{n-1})}{2^{n+1} - 2^n}\...

Simplify \(\frac{3(2^{n+1}) - 4(2^{n-1})}{2^{n+1} - 2^n}\)

A.

2n+1

B.

2n-1

C.

4

D.

1/4

Correct answer is C

Start by expanding \(\frac{3(2^{n+1}) - 4(2^{n-1})}{2^{n+1} - 2^n}\):

\(\frac{3 \times 2^n \times 2^1 - 2^2 \times 2^n \times 2^{-1}}{2^n \times 2 - 2^n}\)

NUMERATOR : 2\(^n\) (  3\(^1\) X 2\(^1\)  -  2\(^2\) X 2\(^-1\) )

--> 2\(^n\) ( 3 X 2 — 4 X \(\frac{1}{2}\) )

--> 2\(^n\) ( 6 - 2 ) 

--> 2\(^n\) (4)

DENOMINATOR : 2\(^n\) ( 2\(^1\)  -  1 )

--> 2\(^n\) ( 2 - 1)

  --> 2\(^n\)

 

: [ 2\(^n\) ( 4) ] ÷ 2\(^n\)

= 4