Author 
Message 
TAGS:

Hide Tags

Director
Status: Finally Done. Admitted in Kellogg for 2015 intake
Joined: 25 Jun 2011
Posts: 527
Location: United Kingdom
Concentration: International Business, Strategy
GPA: 2.9
WE: Information Technology (Consulting)

For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
12 Dec 2011, 05:52
11
This post received KUDOS
99
This post was BOOKMARKED
Question Stats:
73% (01:10) correct 27% (00:54) wrong based on 1365 sessions
HideShow timer Statistics
For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b? A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x Can someone please tell me how to solve this? As OA is not provided I started by substituing the value of f(x) in the answer choice but got stuck. Can someone please help?
Official Answer and Stats are available only to registered users. Register/ Login.
_________________
Best Regards, E.
MGMAT 1 > 530 MGMAT 2> 640 MGMAT 3 > 610 GMAT ==> 730



Manager
Joined: 12 Jul 2011
Posts: 138
Concentration: Operations, Strategy
WE: Engineering (Telecommunications)

Re: function F(x) [#permalink]
Show Tags
12 Dec 2011, 06:47
11
This post received KUDOS
6
This post was BOOKMARKED
Question asks you to check which of the provided options satisfy the equality "f(a+b) = f(a) + f(b)" Answer is E, if you apply f(x) = 3x to f(a+b) then f(a+b) = 3(a+b) = 3a 3b f(a) = 3a f(b) = 3b f(a) + f(b) = 3a 3b = f(a+b) Hope I am clear.



Manager
Joined: 09 Nov 2011
Posts: 127

Re: function F(x) [#permalink]
Show Tags
22 Dec 2011, 09:08
2
This post received KUDOS
1
This post was BOOKMARKED
f(a+b) has to be equal to f(a) + f(b) A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x A) f(x) = x^2 f(a) = a^2; f(b)=b^2 f(a+b) = (a+b)^2 = a^2+b^2 +2ab f(a) +f(b) = a^2 + b^2 <> f(a+b) so on and so forth...each option will lead to the same result except for E Moreover, just by observing it can be found out the square roots, sqaures and x in the denominator will not be correct answers hence just try with E and you can find out..
_________________
Time to play the game...



Math Expert
Joined: 02 Sep 2009
Posts: 43804

Re: function F(x) [#permalink]
Show Tags
15 Jan 2012, 15:06
51
This post received KUDOS
Expert's post
85
This post was BOOKMARKED
Responding to a PM. For which of the following functions is f(a+b)= f(a)+f(b) for all positive numbers a and b?A. \(f(x)=x^2\) B. \(f(x)= x+1\) C. \(f(x) = \sqrt{x}\) D. \(f(x)=\frac{2}{x}\) E. \(f(x) = 3x\) A. \(f(a+b)=(a+b)^2=a^2+2ab+b^2\neq{f(a)+f(b)}=a^2+b^2\) B. \(f(a+b)=(a+b)+1\neq{f(a)+f(b)}=a+1+b+1\) C. \(f(a+b)=\sqrt{a+b}\neq{f(a)+f(b)}=\sqrt{a}+\sqrt{b}\). D. \(f(a+b)=\frac{2}{a+b}\neq{f(a)+f(b)}=\frac{2}{a}+\frac{2}{b}\). E. \(f(a+b)=3(a+b)=3a3b=f(a)+f(b)=3a3b\). Correct. Answer: E. OR, as f(a+b)= f(a)+f(b) must be true for all positive numbers a and b, then you can randomly pick particular values of a and b and check for them: For example: \(a=2\) and \(b=3\) A. \(f(a + b) = f(5) = 5^2 = 25\neq{f(a) + f(b) = f(2) + f(3) = 2^2 + 3^2 = 13}\) B. \(f(a + b) = f(5) = 5 + 1 = 6\neq{f(a) + f(b) = f(2) + f(3) = (2 + 1) + (3 + 1) = 7}\) C. \(f(a + b)=f(5)=\sqrt{5}\neq{f(a) + f(b)=f(2)+f(3)=\sqrt{2}+\sqrt{3}}\) D. \(f(a + b)=f(5)=\frac{2}{5}\neq{f(a)+f(b)=f(2)+f(3)=\frac{2}{2}+\frac{2}{3}=\frac{5}{3}}\) E. \(f(a + b)=f(5)=3*(5) =15=f(a)+f(b)=f(2)+f(3)=3*(2)3*(3)=15\). Correct. It might happen that for some choices of a and b other options may be "correct" as well. If this happens just pick some other numbers and check again these "correct" options only. Similar questions to practice: function85751.htmlfunctionsproblemneedhelp93184.htmlletthefunctiongabfafb143311.htmlHope it helps.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
What are GMAT Club Tests? Extrahard Quant Tests with Brilliant Analytics



Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 7938
Location: Pune, India

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
16 Jan 2012, 01:00
15
This post received KUDOS
Expert's post
11
This post was BOOKMARKED
enigma123 wrote: For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b? A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x
Can someone please tell me how to solve this? As OA is not provided I started by substituing the value of f(x) in the answer choice but got stuck. Can someone please help? You can save time by using an intuitive method. Look for the expression that satisfies the distributive property i.e. x * (y + z) = (x * y) + (x * z) When you put (a+b), it should give you individual functions in a and b which means that you will get two separate, comparable terms in a and b. Squares, roots, addition and division by the variable does not satisfy the distributive property. Multiplication does. So check for option (E) first. One rule of thumb  in such questions, try the options which have multiplication/addition first. These two operators have various properties which make such relations possible.
_________________
Karishma Veritas Prep  GMAT Instructor My Blog
Get started with Veritas Prep GMAT On Demand for $199
Veritas Prep Reviews



Director
Joined: 22 Mar 2011
Posts: 608
WE: Science (Education)

Re: Function Problem [#permalink]
Show Tags
07 Sep 2012, 22:17
2
This post received KUDOS
1
This post was BOOKMARKED
BigUp wrote: Hello GmatClub,
Could someone please help me to understand this gmatprep question? Thanks!
For which of the following functions is f(a+b) = f(a)+f(b) for all positive numbers a and b?
f(x)=x^2 f(x)=x+1 f(x)=sqrt(x) f(x)=2/x f(x)=3x First, a remark: \(a\) and \(b\) are considered positive because the function in C, the square root is not defined for negative numbers and the function in D is not defined for \(x=0\) (\(x\) being in the denominator). The other functions are defined for any real number. For each function, we translate the given equality and check whether is holds for any positive \(a\) and \(b\). If the equality holds for any \(a\) and \(b\), we should get an identity, which means the same expression on both sides of the equal sign. For \(f(a+b)\) we take the expression of any of the given functions and replace \(x\) by \((a+b)\). (A) \((a+b)^2=a^2+b^2\) or \(a^2+2ab+b^2=a^2+b^2\). Necessarily \(ab=0\), which cannot hold, \(a\) an \(b\) being positive. NO (B) \(a+b+1=a+1+b+1\) gives \(1=2\), impossible. NO (C) \(\sqrt{a+b}=\sqrt{a}+\sqrt{b}\) NO (check for example \(a=b=1\)) (D) \(\frac{2}{a+b}=\frac{2}{b}+\frac{2}{b}\) NO (again, check for \(a=b=1\)) (E) \(3(a+b)=3a+(3b)\) or \(3a3b=3a3b\) YES!!! Answer E.
_________________
PhD in Applied Mathematics Love GMAT Quant questions and running.



Senior Manager
Joined: 13 Aug 2012
Posts: 456
Concentration: Marketing, Finance
GPA: 3.23

For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
20 Dec 2012, 22:06
2
This post received KUDOS
2
This post was BOOKMARKED
Best to answer this with tinywinie numbers such as a=1, b=1 and a+b=1... A. (1) + (1) = 4 OUT! B. (1+1) + (1+1) = 3 OUT! C. 1 + 1 = \(\sqrt{2}\) OUT! D. 2/1 + 2/1 = 2/2 OUT! E. 3(1) 3(1) = 3(2) BINGO! Answer: E
_________________
Impossible is nothing to God.



Math Expert
Joined: 02 Sep 2009
Posts: 43804

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
08 Jul 2013, 00:10



Math Expert
Joined: 02 Aug 2009
Posts: 5651

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
27 Feb 2015, 02:27
sagarag wrote: For which of the following functions is F(a+b) = f(a) + f(b) for all positives numbers a and b?
A) f(x) = x^2 B) f(x) = x+1 C) f(x) = x^1/2 D) f(x) = 2/x e) f(x) = 3x hi sagar.. you can eliminate the choices by looking at the choices.. the answer cannot be a variable added or subtracted with a constant.. since that value will get added/subtracted twice on right side... B is out it cannot be a variable multiplied with another variable or with self.. A and C out.. the answer can be a variable multiplied or divided by a constant... D is out as a constant is divided by variable.. E follows the above rule ans E.. you can also find answer by testing values .. take E for example.. since f(x) = 3x, f(a) = 3a f(b) = 3b.. f(a+b)=3(a+b)=3a+(3b)=f(a)+f(b)... E is the ans
_________________
Absolute modulus :http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
BANGALORE/



Manager
Joined: 21 Jan 2014
Posts: 99
GPA: 4

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
15 Jan 2016, 06:37
Bunuel wrote: Responding to a PM. For which of the following functions is f(a+b)= f(a)+f(b) for all positive numbers a and b?A. \(f(x)=x^2\) B. \(f(x)= x+1\) C. \(f(x) = \sqrt{x}\) D. \(f(x)=\frac{2}{x}\) E. \(f(x) = 3x\) A. \(f(a+b)=(a+b)^2=a^2+2ab+b^2\neq{f(a)+f(b)}=a^2+b^2\) B. \(f(a+b)=(a+b)+1\neq{f(a)+f(b)}=a+1+b+1\) C. \(f(a+b)=\sqrt{a+b}\neq{f(a)+f(b)}=\sqrt{a}+\sqrt{b}\). D. \(f(a+b)=\frac{2}{a+b}\neq{f(a)+f(b)}=\frac{2}{a}+\frac{2}{b}\). E. \(f(a+b)=3(a+b)=3a3b=f(a)+f(b)=3a3b\). Correct. Answer: E. OR, as f(a+b)= f(a)+f(b) must be true for all positive numbers a and b, then you can randomly pick particular values of a and b and check for them: For example: \(a=2\) and \(b=3\) A. \(f(a + b) = f(5) = 5^2 = 25\neq{f(a) + f(b) = f(2) + f(3) = 2^2 + 3^2 = 13}\) B. \(f(a + b) = f(5) = 5 + 1 = 6\neq{f(a) + f(b) = f(2) + f(3) = (2 + 1) + (3 + 1) = 7}\) C. \(f(a + b)=f(5)=\sqrt{5}\neq{f(a) + f(b)=f(2)+f(3)=\sqrt{2}+\sqrt{3}}\) D. \(f(a + b)=f(5)=\frac{2}{5}\neq{f(a)+f(b)=f(2)+f(3)=\frac{2}{2}+\frac{2}{3}=\frac{5}{3}}\) E. \(f(a + b)=f(5)=3*(5) =15=f(a)+f(b)=f(2)+f(3)=3*(2)3*(3)=15\). Correct. It might happen that for some choices of a and b other options may be "correct" as well. If this happens just pick some other numbers and check again these "correct" options only. Similar questions to practice: function85751.htmlfunctionsproblemneedhelp93184.htmlletthefunctiongabfafb143311.htmlHope it helps. I always get confused with these kind of questions and I like the method to pick numbers to check whether answer choices are equal to the main statement.



Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 7938
Location: Pune, India

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
15 Jan 2016, 08:59
pepo wrote: Bunuel wrote: Responding to a PM. For which of the following functions is f(a+b)= f(a)+f(b) for all positive numbers a and b?A. \(f(x)=x^2\) B. \(f(x)= x+1\) C. \(f(x) = \sqrt{x}\) D. \(f(x)=\frac{2}{x}\) E. \(f(x) = 3x\) A. \(f(a+b)=(a+b)^2=a^2+2ab+b^2\neq{f(a)+f(b)}=a^2+b^2\) B. \(f(a+b)=(a+b)+1\neq{f(a)+f(b)}=a+1+b+1\) C. \(f(a+b)=\sqrt{a+b}\neq{f(a)+f(b)}=\sqrt{a}+\sqrt{b}\). D. \(f(a+b)=\frac{2}{a+b}\neq{f(a)+f(b)}=\frac{2}{a}+\frac{2}{b}\). E. \(f(a+b)=3(a+b)=3a3b=f(a)+f(b)=3a3b\). Correct. Answer: E. OR, as f(a+b)= f(a)+f(b) must be true for all positive numbers a and b, then you can randomly pick particular values of a and b and check for them: For example: \(a=2\) and \(b=3\) A. \(f(a + b) = f(5) = 5^2 = 25\neq{f(a) + f(b) = f(2) + f(3) = 2^2 + 3^2 = 13}\) B. \(f(a + b) = f(5) = 5 + 1 = 6\neq{f(a) + f(b) = f(2) + f(3) = (2 + 1) + (3 + 1) = 7}\) C. \(f(a + b)=f(5)=\sqrt{5}\neq{f(a) + f(b)=f(2)+f(3)=\sqrt{2}+\sqrt{3}}\) D. \(f(a + b)=f(5)=\frac{2}{5}\neq{f(a)+f(b)=f(2)+f(3)=\frac{2}{2}+\frac{2}{3}=\frac{5}{3}}\) E. \(f(a + b)=f(5)=3*(5) =15=f(a)+f(b)=f(2)+f(3)=3*(2)3*(3)=15\). Correct. It might happen that for some choices of a and b other options may be "correct" as well. If this happens just pick some other numbers and check again these "correct" options only. Similar questions to practice: function85751.htmlfunctionsproblemneedhelp93184.htmlletthefunctiongabfafb143311.htmlHope it helps. I always get confused with these kind of questions and I like the method to pick numbers to check whether answer choices are equal to the main statement. Here are a couple of posts on functions. They could help you. http://www.veritasprep.com/blog/2015/03 ... songmat/http://www.veritasprep.com/blog/2015/03 ... questions/
_________________
Karishma Veritas Prep  GMAT Instructor My Blog
Get started with Veritas Prep GMAT On Demand for $199
Veritas Prep Reviews



Director
Status: Professional GMAT Tutor
Affiliations: AB, cum laude, Harvard University (Class of '02)
Joined: 10 Jul 2015
Posts: 515
Location: United States (CA)
Age: 38
GMAT 1: 770 Q47 V48 GMAT 2: 730 Q44 V47 GMAT 3: 750 Q50 V42
GRE 1: 337 Q168 V169
WE: Education (Education)

For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
06 Apr 2016, 12:23
1
This post was BOOKMARKED
Attached is a visual that should help. Alternate method: plug in a=1 and b=1 to make the math easier.
Attachments
Screen Shot 20160804 at 6.53.30 PM.png [ 112.94 KiB  Viewed 60986 times ]
Screen Shot 20160804 at 7.22.53 PM.png [ 792.38 KiB  Viewed 61049 times ]
IMG_1002.JPG [ 324.37 KiB  Viewed 60965 times ]
_________________
Harvard grad and 770 GMAT scorer, offering highquality private GMAT tutoring, both inperson and online via Skype, since 2002.
You can download my official testtaker score report directly from the Pearson Vue website: https://tinyurl.com/y8zh6qby Date of Birth: 09 December 1979.
GMAT Action Plan  McElroy Tutoring



Manager
Status: love the club...
Joined: 24 Mar 2015
Posts: 248

For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
11 Oct 2017, 10:20
VeritasPrepKarishma wrote: enigma123 wrote: For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b? A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x
Can someone please tell me how to solve this? As OA is not provided I started by substituing the value of f(x) in the answer choice but got stuck. Can someone please help? You can save time by using an intuitive method. Look for the expression that satisfies the distributive property i.e. x * (y + z) = (x * y) + (x * z) When you put (a+b), it should give you individual functions in a and b which means that you will get two separate, comparable terms in a and b. Squares, roots, addition and division by the variable does not satisfy the distributive property. Multiplication does. So check for option (E) first. One rule of thumb  in such questions, try the options which have multiplication/addition first. These two operators have various properties which make such relations possible. a golden rule of thumb: trying multiplication/ addition first I have applied it to couple of cases, and the rule duly worked, saving time thanks, mam



Manager
Status: love the club...
Joined: 24 Mar 2015
Posts: 248

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
11 Oct 2017, 10:32
enigma123 wrote: For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b?
A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x
Can someone please tell me how to solve this? As OA is not provided I started by substituing the value of f(x) in the answer choice but got stuck. Can someone please help? hi A: (a + b) ^ 2 is not equal to a^ + b ^2, discard B: a + b + 1 is not equl to b + 1 + a + 1, discard C: square rootover (a + b) is not equal to rootover a + rootover b , discard D: 2/ a+b is not equal to 2/a + 2/b E: 3 (a + b) is equal to 3a 3b, so this is the correct choice thanks



Intern
Joined: 10 Feb 2016
Posts: 1
GMAT 1: 470 Q36 V19 GMAT 2: 570 Q44 V24

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
08 Jan 2018, 10:32
For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b? A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x I substituted x in a and b > f(a+b)= f(a) + f(b) > f(x+x)= f(x) + f(x) > f(2x)= 2 f(x) so I have to find the option that satisfies this equation. a) f(2x)= 4x^2 vs 2f(x)=2x^2 ( Not equal) b) f(2x)=2x+1 vs 2f(x)= 2x+2 ( Not equal) c) f(2x)= sqrt 2*sqrt x vs 2f(x)= 2 * sqrt x (Not equal) d) f(2x)=1/x vs 2f(x)= 4/x (Not equal) e) f(2x)=6x vs 2f(x)= 6x (equal) Therefore e) is the answer.
_________________
“Vision is not enough, it must be combined with venture. It is not enough to stare up the steps, we must step up the stairs.”



SVP
Joined: 11 Sep 2015
Posts: 2049
Location: Canada

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
06 Feb 2018, 14:50
enigma123 wrote: For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b?
A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x
One approach is to plug in numbers. Let's let a = 1 and b = 1So, the question becomes, "Which of the following functions are such that f(1+1) = f(1) + f(1)?" In other words, for which function does f(2) = f(1) + f(1)?A) If f(x)=x², does f( 2) = f( 1) + f( 1)? Plug in to get: 2² = 1² + 1²? (No, doesn't work) So, it is not the case that f( 2) = f( 1) + f( 1), when f(x)=x² B) If f(x)=x+1, does f( 2) = f( 1) + f( 1)? Plug in to get: 2+1 = 1+1 + 1+1? (No, doesn't work) So, it is not the case that f( 2) = f( 1) + f( 1) . . . A, B, C and D do not work. So, at this point, we can conclude that E must be the correct answer. Let's check E anyway (for "fun") E) If f(x)=3x, does f( 2) = f( 1) + f( 1)? Plugging in 2 and 1 we get: (3)( 2) = (3)( 1) + (3)( 1) Yes, it works The correct answer is E Cheers, Brent
_________________
Brent Hanneson – Founder of gmatprepnow.com



Target Test Prep Representative
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 1975

Re: For which of the following functions is f(a+b)=f(b)+f(a) [#permalink]
Show Tags
12 Feb 2018, 11:01
enigma123 wrote: For which of the following functions is f(a+b)=f(b)+f(a) for all positive numbers a and b?
A. f(x)=x^2 B. f(x)=x+1 C. f(x)=√x D. f(x)=2/x E. f(x)=3x We need to determine when f(a + b) = f(a) + f(b). Before we evaluate each answer choice it may be easier to use numerical values for a and b. If we let a = 1 and b = 2, our new function looks like: f(1 + 2) = f(1) + f(2) f(3) = f(1) + f(2) So we must determine when the output of f(3) equals the sum of the outputs of f(1) and f(2). Let’s now evaluate each answer choice. A) f(x) = x^2 f(3) = 3^2 = 9 f(1) = 1^2 = 1 f(2) = 2^2 = 4 Since 9 does not equal 1 + 4, choice A is not correct. B) f(x) = x + 1 f(3) = 3 + 1 = 4 f(1) = 1 + 1 = 2 f(2) = 2 + 1 = 3 Since 4 does not equal 2 + 3, choice B is not correct. C) f(x) = √x f(3) = √3 f(1) = √1 = 1 f(2) = √2 Since √3 does not equal 1 + √2, choice C is not correct. D) f(x) = 2/x f(3) = 3/2 f(1) = 2/1 = 2 f(2) = 2/2 = 1 Since 3/2 does not equal 2 + 1, choice D is not correct. Since we have eliminated all the other answer choices, we know the answer is E. However, let’s show as an exercise that answer choice E satisfies the given property for our choice of numbers: E) f(x) = 3x f(3) = 3(3) = 9 f(1) = 3(1) = 3 f(2) = 3(2) = 6 Since 9 equals 3 + (6), choice E is correct. Answer: E
_________________
Jeffery Miller
Head of GMAT Instruction
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions




Re: For which of the following functions is f(a+b)=f(b)+f(a)
[#permalink]
12 Feb 2018, 11:01






