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Which is greater a^4a^5 or (a^3)^2
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28 Dec 2018, 11:15
28 Dec 2018, 11:15
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Question Stats:
46% (00:20) correct
53% (00:11) wrong based on 240 sessions
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Quantity A |
Quantity B |
\(a^4a^5\) |
\((a^3)^2\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
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Re: Which is greater a^4a^5 or (a^3)^2
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30 Dec 2018, 11:04
30 Dec 2018, 11:04
1
Carcass wrote:
Quantity A |
Quantity B |
\(a^4a^5\) |
\((a^3)^2\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
GIVEN:
Quantity A: (a^4)(a^5)
Quantity B: (a^3)^2
Simplify each expression to get:
Quantity A: a^9
Quantity B: a^6
Let's test some values
If a = 0, we get:
Quantity A: 0^9 = 0
Quantity B: 0^6 = 0
In this case, the two quantities are EQUAL
If a = 2, we get:
Quantity A: 2^9 = 512
Quantity B: 2^6 = 64
In this case, the Quantity A is GREATER
Answer: D
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Re: Which is greater a^4a^5 or (a^3)^2
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30 Dec 2018, 20:22
30 Dec 2018, 20:22
Expert Reply
Carcass wrote:
Quantity A |
Quantity B |
\(a^4a^5\) |
\((a^3)^2\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Our answer will come if we can know \(a^4a^5-(a^3)^2....a^6(a^3-1)\), which is same as A-B, is positive, negative or 0..
Now a^6 is always positive or 0 ...
But \(a^3-1\) can be positive when a is 2, it can be negative when a is -1..
So we cannot determine..
D
