BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

PS question

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 484
Joined: Sun Jul 30, 2006 7:01 pm
Thanked: 2 times
Followed by:1 members

PS question

by magical cook » Sun Nov 11, 2007 11:32 pm
The function f is defined by f(x) = √x – 10 for all positive numbers x. If u = f(t) for some positive numbers t and u. What is t in terms of u?


A. √(u+10)
B. (√u + 10)^2
C. √(u^2+10)
D. (u + 10)^2
E. (u^2 + 10)^2


For some reason I got E but answer is D.... Can anyon confirm?
Top
Source: — Problem Solving |
Legendary Member
Posts: 645
Joined: Wed Sep 05, 2007 4:37 am
Location: India
Thanked: 34 times
Followed by:5 members

by camitava » Mon Nov 12, 2007 12:37 am
magical cook, OA is correct one and it should be D. Because,
f(t) = t^1/2 - 10 = s
or t^1/2 = s + 10
so t = (s + 10) ^ 2
So here comes D.
Correct me If I am wrong


Regards,

Amitava
Top
Master | Next Rank: 500 Posts
Posts: 484
Joined: Sun Jul 30, 2006 7:01 pm
Thanked: 2 times
Followed by:1 members

by magical cook » Mon Nov 12, 2007 8:14 am
Thank you,

I thin I mislead the question as square root for both x+10 instead of only x
Top
Post new topic Post Reply
• Page 1 of 1