Author 
Message 
TAGS:

Hide Tags

Manager
Joined: 15 Jan 2011
Posts: 108

If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? [#permalink]
Show Tags
19 Aug 2013, 10:38
1
This post received KUDOS
5
This post was BOOKMARKED
Question Stats:
74% (01:34) correct 26% (01:57) wrong based on 337 sessions
HideShow timer Statistics
If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? (A) – 10 (B) – 8 (C) – 6 (D) 0 (E) 4
Official Answer and Stats are available only to registered users. Register/ Login.
Last edited by Bunuel on 19 Aug 2013, 10:52, edited 1 time in total.
Edited the question and added the OA



Director
Joined: 14 Dec 2012
Posts: 832
Location: India
Concentration: General Management, Operations
GPA: 3.6

Re: If g(x) = ax5 + bx3 + 1 [#permalink]
Show Tags
19 Aug 2013, 10:51
1
This post received KUDOS
4
This post was BOOKMARKED
Galiya wrote: If g(x) = ax5 + bx3 + 1, and g(5) = 10, then g(–5) =?
(A) – 10 (B) – 8 (C) – 6 (D) 0 (E) 4 given:\(g(5) = 10\) therefore \(a*5^5 + b5^3 + 1 = 10\) \(a*5^5 + b5^3 = 9\) ..................................(1 \(g(5) = a*5^5  b5^3 + 1\) \(= (a*5^5 + b5^3)+1\) now using 1 \(g(5) = 9 + 1 = 8\) hence B
_________________
When you want to succeed as bad as you want to breathe ...then you will be successfull....
GIVE VALUE TO OFFICIAL QUESTIONS...
GMAT RCs VOCABULARY LIST: http://gmatclub.com/forum/vocabularylistforgmatreadingcomprehension155228.html learn AWA writing techniques while watching video : http://www.gmatprepnow.com/module/gmatanalyticalwritingassessment : http://www.youtube.com/watch?v=APt9ITygGss



Senior Manager
Joined: 10 Jul 2013
Posts: 324

Re: If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? [#permalink]
Show Tags
19 Aug 2013, 12:39
1
This post received KUDOS
Galiya wrote: If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =?
(A) – 10 (B) – 8 (C) – 6 (D) 0 (E) 4 g(5) = 10 or, 5^5 a + 5^3 b + 1 = 10 or, 5^5 a + 5^3 b = 9 g(5) = 5^5 a  5^3 b + 1 =  (5^5 a + 5^3 b) + 1 =  9 + 1 =  8 = (B)
_________________
Asif vai.....



NonHuman User
Joined: 09 Sep 2013
Posts: 13818

Re: If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? [#permalink]
Show Tags
13 Sep 2014, 21:45
Hello from the GMAT Club BumpBot! Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up  doing my job. I think you may find it valuable (esp those replies with Kudos). Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources



NonHuman User
Joined: 09 Sep 2013
Posts: 13818

Re: If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? [#permalink]
Show Tags
04 Aug 2016, 21:02
Hello from the GMAT Club BumpBot! Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up  doing my job. I think you may find it valuable (esp those replies with Kudos). Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources



Manager
Joined: 07 Jul 2016
Posts: 79
GPA: 4

If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? [#permalink]
Show Tags
04 Aug 2016, 21:24
Galiya wrote: If \(g(x) = ax^5 + bx^3 + 1\), and \(g(5) = 10\), then \(g(–5) =?\) When raising a number to an odd power, if we negate the number, we negate the sign of the result. \(ax^5 + bx^3 = 9 \, (x:5)\\ ax^5 + bx^3 = 9 \, (x:5)\) \(9 + 1 = 8\)
_________________
Please press +1 Kudos if this post helps.



Board of Directors
Joined: 17 Jul 2014
Posts: 2729
Location: United States (IL)
Concentration: Finance, Economics
GPA: 3.92
WE: General Management (Transportation)

Re: If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =? [#permalink]
Show Tags
07 Apr 2017, 14:23
it look me almost 3 minutes to solve it... first: g(5) = a*5^5 + b*5^3 +1 = 10 a*5^5 + b*5^3 = 9 5^3 * (a*5^2 + b) = 9 125 * (25a + b) = 9 25a + b = 9/125
now g(5) = a*5^5 + b*5^3 +1 we can factor out 5^3 5^3 * (a*5^2 +b) +1 125*(25a + b) +1
we know 25a + b = 9/125 125* 25a + b = 9 125*(25a + b) +1 = 8
answer is B.




Re: If g(x) = ax^5 + bx^3 + 1, and g(5) = 10, then g(–5) =?
[#permalink]
07 Apr 2017, 14:23






