If f(x) = k(x - k) and k is a constant, what is the value of f(4) - f(3), in terms of k?
(A) 1
(B) k
(C) 7k - 1
(D) k^2 + k
(E) k^2 - k
Answer: B
Source: GMAT Hacks
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If f(x) = k(x - k) and k is a constant, what is the value of f(4)
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BTGModeratorVI
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Given: f(x) = k(x - k)BTGModeratorVI wrote: ↑Tue Feb 18, 2020 11:04 amIf f(x) = k(x - k) and k is a constant, what is the value of f(4) - f(3), in terms of k?
(A) 1
(B) k
(C) 7k - 1
(D) k^2 + k
(E) k^2 - k
Answer: B
Source: GMAT Hacks
So, for example, f(9) = k(9 - k) = 9k - k²
The question asks for the value of f(4) - f(3)
f(4) - f(3) = [k(4 - k)] - [k(3 - k)]
= [4k - k²] - [3k - k²]
= k
Answer: B
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Brent
Brent Hanneson - Creator of GMATPrepNow.com
