how to make it on calculator or what is the value of tan2?
To find tan2 you first find tan, then you square that.
tan2 30° = (tan 30°)x(tan 30°)
Tangent is a function, and tan2 have no value.
Of course Max is correct, there has to be an angle there. :)
or
(tan30)^2 = 1/3
The calc changes it to tan30^2 but that is ok :)
(tan(30))^2 = 0.3333333333337655
It should just be 1/3 so there is some rounding error.