If f(x) = (x + √3)^4, what is the range of the function f(

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Source:- MGMAT equations

If f(x) = (x + √3)^4, what is the range of the function f(x) ?

A. √3 < f(x) < 4
B. f(x) >= 0
C. f(x) < 0
D. f(x) not equal to 0

Answer is B

Why A cannot be the answer ?

Thanks & Regards
Vinni
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by GMATGuruNY » Wed Dec 05, 2012 2:35 am
vinni.k wrote:Source:- MGMAT equations

If f(x) = (x + √3)^4, what is the range of the function f(x) ?

A. √3 < f(x) < 4
B. f(x) >= 0
C. f(x) < 0
D. f(x) not equal to 0

Answer is B

Why A cannot be the answer ?

Thanks & Regards
Vinni
The RANGE is composed of ALL possible values of f(x).
If x = -√3, then f(-√3) = (-√3 + √3)� = 0.
Since the correct answer must include 0 within its range, eliminate A, C and D.

The correct answer is B.

(x + √3)� can be equal to any NONNEGATIVE value.
Thus, the range of f(x) = (x + √3)� is any value greater than or equal to 0.
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by vinni.k » Wed Dec 05, 2012 4:28 am
GMATGuruNY wrote: The RANGE is composed of ALL possible values of f(x).
If x = -√3, then f(-√3) = (-√3 + √3)� = 0.
Since the correct answer must include 0 within its range, eliminate A, C and D.

The correct answer is B.

(x + √3)� can be equal to any NONNEGATIVE value.
Thus, the range of f(x) = (x + √3)� is any value greater than or equal to 0.
Thanks Mitch. As always you are the best. Making things easier to understand.

Regards
Vinni