can someone help me figure this out?
experts pls help..
tough functions
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Source: Beat The GMAT — Problem Solving |
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Talkativetree
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If function f(x) satisfies f(x) - f(x^2) for all x, which of the followong must be true?
A F(4) = F(2)*F(2)
B F(16) - F(2) = 0
C F(-2) +F(4) =0
D F(-3) = 3F(3)
E F(0) = 0
I wrote it out as f(x) = f(x) - f(x^2)
if you plug f(x)-f(x^2) into the different equations, you'll see that for B.
f(x) - f(x^2) - [f(x) - f(x^2)]=0
f(x) - f(x) + f(x^2) - f(x^2)=0
or 0=0
A F(4) = F(2)*F(2)
B F(16) - F(2) = 0
C F(-2) +F(4) =0
D F(-3) = 3F(3)
E F(0) = 0
I wrote it out as f(x) = f(x) - f(x^2)
if you plug f(x)-f(x^2) into the different equations, you'll see that for B.
f(x) - f(x^2) - [f(x) - f(x^2)]=0
f(x) - f(x) + f(x^2) - f(x^2)=0
or 0=0
