If a is a positive integer, then 2^a + 2^(a + 1) =

Question

If a is a positive integer, then  2^a + 2^{(a + 1)} =

A. 3^(a + 1)

B. 2^(a + 1)

C. 2a

D. 2a^(a + 1)

E. 3(2^a)

Abhishek009 · Accepted Answer

2^a + 2^{(a + 1)}

=  2^a + 2^a * 2

=  2^a ( 1 + 2 )

=  3(2^a)

Hence, answer will be (E)  3(2^a)

peachfuzz · Answer

If a is a positive integer, then 2^a + 2^(a + 1) =

2^a + 2^(a + 1) 
2^a(1+2)
2^a(3)

E. 3(2^a)

stampap · Answer

can someone elaborate please?

alados14 · Answer

2^a+2^(a+1)= 2^a+ 2^a 2^1= 2^a (1+2)=2^a×3. E

Sent from my SAMSUNG-SM-G935A using  GMAT Club Forum mobile app

peachfuzz · Answer

the trick here is the distribution - review your exponent rules

stampap · Answer

thank you guys, i also reviewed the rules . It is much more clear now

JeffTargetTestPrep · Answer

We must simplify the following expression:

2^a + 2^(a + 1)

2^a + 2 x 2^a

2^a(1 + 2)

3(2^a)

Answer: E

Grid · Answer

Please let me know what property you used to simplify the expression 2^3a to the expression 3(2^a)
Thanks

preetamsaha · Answer

2^a+2^(a+1)

= 2^a+2^a∗2

= 2^a(1+2)

= 3(2^a)

correct answer is (E)

v12345 · Answer

2^a + 2^{(a + 1)} = 2^a + 2^a*2 = 2^a(1 + 2) = 3(2^a)

Hence the correct answer is E.

bumpbot · Answer

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If a is a positive integer, then 2^a + 2^(a + 1) =

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If a is a positive integer, then 2^a + 2^(a + 1) =

Prep Toolkit

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