Functions

How do I solve this:
f(x)=cos(logx)
find f(x)f(y)-[f(x/y)+f(xy)]/2

3 Answers

206

Sayantan Hazra ·2013-04-22 05:06:31

Hint:
Use the properties of logarithms here to evaluate [f(x/y) + f(xy)]....and then you can solve the rest.

996

Swarna Kamal Dhyawala ·2013-04-22 05:15:30

f(x)f(y)-[f(x/y)+f(xy)]/2 = cos(logx)cos(logy)-[cos(logx-logy)+cos(logx+logy)]
now take logx=A and logy=B and solve
i thimk answer is 0

150

Shreya Sharma ·2013-04-22 05:38:33

Yes even I got the answer as 0 :)

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