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Sub 505 Level|   Algebra|   Exponents|      
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Bunuel
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If a is a positive integer, then 3^a + 3^(a +1) = 03 Dec 2014, 08:24
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E
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83% (00:51) correct 17% (01:07) wrong based on 222 sessions

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Tough and Tricky questions: Exponents.



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

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

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E
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If a is a positive integer, then 3^a + 3^(a +1) = Updated on: 03 Dec 2014, 21:18
Originally posted by omegacube on 03 Dec 2014, 08:33.
Last edited by omegacube on 03 Dec 2014, 21:18, edited 1 time in total.
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3^a + 3^(a +1)
= 3^a + 3.3^a
= 3^a(1 + 3)
= 4(3^a)

Hence E
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If a is a positive integer, then 3^a + 3^(a +1) = 03 Dec 2014, 12:32
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3^a + 3^(a+1) = 3^a + 3^a*3 = 3^a(1+3) = 4*3^a.

Choice E
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If a is a positive integer, then 3^a + 3^(a +1) = 03 Dec 2014, 13:55
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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)
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If a is a positive integer, then 3^a + 3^(a +1) = 03 Dec 2014, 21:17
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Answer = E) 4(3^a)

\(3^a + 3^{(a +1)} = 3^a + 3^a * 3 = 3^a (1 + 3) = 4 * 3^a\)
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If a is a positive integer, then 3^a + 3^(a +1) = 03 Dec 2014, 21:43
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3^a + 3^(a +1)
= 3^a + (3^a * 3^1)
= 3^a (1 + 3)
= 3^a(4)

Ans. E) 4(3^a)
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If a is a positive integer, then 3^a + 3^(a +1) = 30 Jan 2017, 14:34
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\(3^{a} + 3^{a+1}\)
\(3^{a} + 3^{a} . 3^{1}\)
\(3^{a}\) x (1 + 3)
\(3^{a}\)x(4)
E
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If a is a positive integer, then 3^a + 3^(a +1) = 30 Jan 2017, 23:57
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3^a + 3^(a +1)
= 3^a + 3.3^a
= 3^a(1 + 3)
= 4(3^a)

Hence E
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If a is a positive integer, then 3^a + 3^(a +1) = 02 Feb 2017, 12:21
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Bunuel

Tough and Tricky questions: Exponents.



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

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

3^a + 3^(a +1)

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

3^a(1 + 3^1)

3^a(4)

Answer: E
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If a is a positive integer, then 3^a + 3^(a +1) = 02 Feb 2017, 12:25
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3^a+3^(a+1)
=3^a+3^a.3
=3^a(1+3)
=3^a.4

Hence (E)
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If a is a positive integer, then 3^a + 3^(a +1) = 05 May 2017, 12:39
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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...

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