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If f is a fraction between −1 and 1, which of the following
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01 Feb 2020, 11:43
01 Feb 2020, 11:43
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33% (01:14) correct
66% (00:58) wrong based on 27 sessions
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If f is a fraction between −1 and 1, which of the following must be true?
A. \(f^7 < f^5\)
B. \(f^6 – f^7 < f^4 – f^5\)
C. \(f^6 + f^7 < f^5 + f^4\)
D. \((–f)^3 < f^3\)
E. \(f^6 < f^4\)
Kudos for the right answer and explanation
A. \(f^7 < f^5\)
B. \(f^6 – f^7 < f^4 – f^5\)
C. \(f^6 + f^7 < f^5 + f^4\)
D. \((–f)^3 < f^3\)
E. \(f^6 < f^4\)
Kudos for the right answer and explanation
Re: If f is a fraction between −1 and 1, which of the following
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03 Feb 2020, 09:35
03 Feb 2020, 09:35
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A: f^7 < f^5 when f is a positive fraction, but when f is negative, f^7 has the smaller absolute value or in other words, is the smaller negative number of the two and therefore greater than f^5 --> not always the case
B: rewrite in f^6*(1-f) < f^4 (1-f) | : (1-f) --> sign doesn't change, since 1-f is always positive (if f is positive, then 0< 1-f < 1 and if f is negative (=-f): 1< 1-(-f) <2)
-->f^6 < f^4 --> f^6 is always smaller than f^4 bc. both have even exponents and thus are positive;
--> CORRECT
C: see B) f^6*(1+f) < f^4*(1+f) --> f^6 is always smaller than f^4 bc. both have even exponents and thus are positive
--> CORRECT
D: if f is a positive fraction, the statement is correct, but if f is negative, -f^3 is positive and therefore greater
E: see B and C: f^6 is always smaller than f^4 bc. both have even exponents and thus are positive (a positive fraction gets smaller, the higher the exponent)
--> CORRECT
--> B, C and E are correct
B: rewrite in f^6*(1-f) < f^4 (1-f) | : (1-f) --> sign doesn't change, since 1-f is always positive (if f is positive, then 0< 1-f < 1 and if f is negative (=-f): 1< 1-(-f) <2)
-->f^6 < f^4 --> f^6 is always smaller than f^4 bc. both have even exponents and thus are positive;
--> CORRECT
C: see B) f^6*(1+f) < f^4*(1+f) --> f^6 is always smaller than f^4 bc. both have even exponents and thus are positive
--> CORRECT
D: if f is a positive fraction, the statement is correct, but if f is negative, -f^3 is positive and therefore greater
E: see B and C: f^6 is always smaller than f^4 bc. both have even exponents and thus are positive (a positive fraction gets smaller, the higher the exponent)
--> CORRECT
--> B, C and E are correct
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Re: If f is a fraction between −1 and 1, which of the following
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12 Feb 2020, 11:15
12 Feb 2020, 11:15
1
Carcass wrote:
If f is a fraction between −1 and 1, which of the following must be true?
A. \(f^7 < f^5\)
B. \(f^6 – f^7 < f^4 – f^5\)
C. \(f^6 + f^7 < f^5 + f^4\)
D. \((–f)^3 < f^3\)
E. \(f^6 < f^4\)
Kudos for the right answer and explanation
A. \(f^7 < f^5\)
B. \(f^6 – f^7 < f^4 – f^5\)
C. \(f^6 + f^7 < f^5 + f^4\)
D. \((–f)^3 < f^3\)
E. \(f^6 < f^4\)
Kudos for the right answer and explanation
ASIDE: I doubt that the GRE test-makers would use the term "fraction" in this case, since 0/1 is considered a fraction (as is 1/1, 2/1, 3/1, etc.) in the GRE Official Guide.
If f = 0/1 (aka 0), then none of the statements are true.
