GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Given 1/2f(x)=f(x/2),
[#permalink]
Updated on: 19 Feb 2018, 02:13
Updated on: 19 Feb 2018, 02:13
3
Bookmarks
00:00
Question Stats:
80% (00:52) correct
20% (01:11) wrong based on 15 sessions
Hide Show timer Statistics
Given \(\frac{1}{2} f(x)= f (\frac{1}{2} * x)\), which of the following is true for all values of f(x)?
A.\(f(x)= 2x+2\)
B.\(f(x)=13x\)
C.\(f(x)=x^2\)
D.\(f(x)=x-10\)
E.\(f(x)=\sqrt{(x-4)}\)
I know the answer is B and I got it by trying each f(x) function. However the answer indicates, "the fastest method is to use logical: since the order of operations says that order does not matter with multiplication and division but does matter between multiplication and addition/subtraction, or multiplication and exponents, choose a function that has only multiplication and/or division."
Could anyone explain this logic? Thank you.
A.\(f(x)= 2x+2\)
B.\(f(x)=13x\)
C.\(f(x)=x^2\)
D.\(f(x)=x-10\)
E.\(f(x)=\sqrt{(x-4)}\)
I know the answer is B and I got it by trying each f(x) function. However the answer indicates, "the fastest method is to use logical: since the order of operations says that order does not matter with multiplication and division but does matter between multiplication and addition/subtraction, or multiplication and exponents, choose a function that has only multiplication and/or division."
Could anyone explain this logic? Thank you.
Originally posted by alihong2010 on 17 Feb 2018, 12:03.
Last edited by Carcass on 19 Feb 2018, 02:13, edited 2 times in total.
Last edited by Carcass on 19 Feb 2018, 02:13, edited 2 times in total.
Edited by Carcass
Re: A question on functions and formulas from Manhattan Prep 5lb
[#permalink]
17 Feb 2018, 16:18
17 Feb 2018, 16:18
alihong2010 wrote:
Given 1/2f(x)=f(x/2), which of the following is true for all values of f(x)?
A.f(x)=2x+2
B.f(x)=13x
C.f(x)=x^2
D.f(x)=x-10
E.f(x)=sqrt(x-4)
I know the answer is B and I got it by trying each f(x) function. However the answer indicates, "the fastest method is to use logical: since the order of operations says that order does not matter with multiplication and division but does matter between multiplication and addition/subtraction, or multiplication and exponents, choose a function that has only multiplication and/or division."
Could anyone explain this logic? Thank you.
A.f(x)=2x+2
B.f(x)=13x
C.f(x)=x^2
D.f(x)=x-10
E.f(x)=sqrt(x-4)
I know the answer is B and I got it by trying each f(x) function. However the answer indicates, "the fastest method is to use logical: since the order of operations says that order does not matter with multiplication and division but does matter between multiplication and addition/subtraction, or multiplication and exponents, choose a function that has only multiplication and/or division."
Could anyone explain this logic? Thank you.
well, since the problem features transformations which feature multiplication (1/2*f(x)) and division (x/2), it's safe to say that the DM part of PEDMAS is used- I guess that leads to trying only equations with DM transformations? I'm not 100% sure either
Re: A question on functions and formulas from Manhattan Prep 5lb
[#permalink]
17 Feb 2018, 16:19
17 Feb 2018, 16:19
alihong2010 wrote:
Given 1/2f(x)=f(x/2), which of the following is true for all values of f(x)?
A.f(x)=2x+2
B.f(x)=13x
C.f(x)=x^2
D.f(x)=x-10
E.f(x)=sqrt(x-4)
I know the answer is B and I got it by trying each f(x) function. However the answer indicates, "the fastest method is to use logical: since the order of operations says that order does not matter with multiplication and division but does matter between multiplication and addition/subtraction, or multiplication and exponents, choose a function that has only multiplication and/or division."
Could anyone explain this logic? Thank you.
A.f(x)=2x+2
B.f(x)=13x
C.f(x)=x^2
D.f(x)=x-10
E.f(x)=sqrt(x-4)
I know the answer is B and I got it by trying each f(x) function. However the answer indicates, "the fastest method is to use logical: since the order of operations says that order does not matter with multiplication and division but does matter between multiplication and addition/subtraction, or multiplication and exponents, choose a function that has only multiplication and/or division."
Could anyone explain this logic? Thank you.
What page in the book was this featured, if you don't mind me asking?
