If a is a positive integer, then 3^a + 3^(a +1) =

Question

Tough and Tricky questions: Exponents.

A) 4^a
B) 3^a − 1
C) 3^(2a) + 1
D) 3^a*(a − 1)
E) 4(3^a)

Kudos for a correct  solution .

Source: Chili Hot GMAT

omegacube · Answer

3^a + 3^(a +1)
= 3^a + 3.3^a
= 3^a(1 + 3)
= 4(3^a)

Hence E

intheend14 · Answer

3^a + 3^(a+1) = 3^a + 3^a*3 = 3^a(1+3) = 4*3^a.

Choice E

bostonbp · Answer

3^a+3^(a+1)
Factor: 3^a(1+3) (because 3^a times 1 is 3^a, and 3^a times 3 is 3^(a+1))
Simplify: 4(3^a)

PareshGmat · Answer

Answer = E) 4(3^a)

3^a + 3^{(a +1)} = 3^a + 3^a * 3 = 3^a (1 + 3) = 4 * 3^a

JJo · Answer

3^a + 3^(a +1) 
= 3^a + (3^a * 3^1) 
= 3^a (1 + 3) 
= 3^a(4)

Ans. E) 4(3^a)

kanusha · Answer

3^{a} + 3^{a+1} 
 3^{a} + 3^{a} . 3^{1} 
 3^{a}  x (1 + 3)
 3^{a} x(4)
E

saadharis · Answer

3^a + 3^(a +1)
= 3^a + 3.3^a
= 3^a(1 + 3)
= 4(3^a)

Hence E

ScottTargetTestPrep · Answer

3^a + 3^(a +1)

3^a + (3^a)(3^1)

3^a(1 + 3^1)

3^a(4)

Answer: E

sjavvadi · Answer

3^a+3^(a+1)
=3^a+3^a.3
=3^a(1+3)
=3^a.4

Hence (E)

sashiim20 · Answer

If a is a positive integer, then 3^a + 3^{(a +1)} = 3^a + 3^ {(a+1)} = 3^a + 3^a * 3^1 = 3^a (1 + 3) = 3^a * 4 = 4( 3^a ) Therefore Answer E... _________________ P.S. Don't forget to give Kudos

If a is a positive integer, then 3^a + 3^(a +1) =

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If a is a positive integer, then 3^a + 3^(a +1) =

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