f(x+y) = f(x) + f(y)

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f(x+y) = f(x) + f(y)

by kunalkulkarni » Sun Feb 10, 2013 5:54 pm
For which of the following functions is
f(x+y) = f(x) + f(y)
for all positive numbers x and y?

f(a) = a^2
f(a) = a+1
f(a) = squareroot(a)
f(a) = 2/a
f(a) = -3a

can anyone please explain me the above problem?

Thanks in advance,
Kunal

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by kunalkulkarni » Sun Feb 10, 2013 8:16 pm
You know GMATGuru, I plugged-in same values of 5,2 and 3. But, I was only stuck at a point where the functions are to be solved!
I realized, what a silly mistake I committed!
Thank you so much!

Cheers,
Kunal