Question 4 (Nov.14th)

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Question 4 (Nov.14th)

by bacali » Fri Nov 14, 2008 12:38 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. √(u2+10)
D. (u + 10)2
E. (u2 + 10)2
Source: — Problem Solving |

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by cramya » Fri Nov 14, 2008 1:06 pm
A. √(u+10)
B. (√u + 10)2
C. √(u2+10)
D. (u + 10)2
E. (u2 + 10)2

Is choice B sqrt(u+10) ^ 2 or (sqrt(u) + 10 ) ^ 2

Similarly is choice C
SQRT(U^2+10) ??

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by dmateer25 » Fri Nov 14, 2008 1:12 pm
u = √t - 10
u+10 = √t
(u +10)^2 = t

IMO D