Maths Olympiad Prep

Library / /37 of 520

Algebra Difficulty 1.8 Junior Find the answer

If f(2x)=22+xf(2x)=\frac{2}{2+x} for all x>0x>0, then 2f(x)=2f(x)=

Pick one

Solution

As f(2x)=22+xf(2x)=\frac{2}{2+x}, we have that f(x)=22+x2f(x)=\frac{2}{2+\frac{x}{2}}. This also means that 2f(x)=42+x22f(x)=\frac{4}{2+\frac{x}{2}} which implies that the answer is E\fbox{E}. ~ samrocksnature
Note: Wait what

Want a route through all this instead of an archive? The track puts 2,000 problems in a working order, from AMC 10 level to the IMO shortlist.

Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.