in the picture you can see the Function.
how many of the features of this Function are correct?

this is the features :
1)f(x)=1 if and only if x=0.5pi
2)f(2)=1
3)f(x)=sqrt3 if and only if x=2pi/3
4)f(-2)=-0.25pi

Sure sure thanks for help :-)

It woyuld make it less confung of all four of these were expressed consistently, in eth form arctan(x) = y, like this:

1) arctan (\frac {\pi} 4) = 1 ?

2) Arctan (1) = 1?

3) arctan (\frac {\pi} {3}) = \sqrt {3} ?

4) arctan (-1) = \frac {-\pi} 4 ?

Now, recall that the arctan function yields an angle, usually expressed in radians. Can you finish this now?

Well I know this "f(-2)=-0.25pi" is correct.
It think this is the only things who is correct here yes?

Thank you

*i think

Here only NO 4 is correct I think.

Right - number 4 is the only correct one.

Thank you :)